Search Results

Search found 4028 results on 162 pages for 'mysqld safe'.

Page 19/162 | < Previous Page | 15 16 17 18 19 20 21 22 23 24 25 26  | Next Page >

• c# function to send safe strings to javascript

  - by Blankman

  is there a c# function that will encode all javastring escape characters?

  Read the article

• is it safe to refactor my django models?

  - by Johnd

  My model is similar to this. Is this ok or should I make the common base class abstract? What are the differcenes between this or makeing it abstract and not having an extra table? It seems odd that there is only one primary key now that I have factored stuff out. class Input(models.Model): details = models.CharField(max_length=1000) user = models.ForeignKey(User) pub_date = models.DateTimeField('date published') rating = models.IntegerField() def __unicode__(self): return self.details class Case(Input): title = models.CharField(max_length=200) views = models.IntegerField() class Argument(Input): case = models.ForeignKey(Case) side = models.BooleanField() is this ok to factor stuff out intpu Input? I noticed Cases and Arguments share a primary Key. like this: CREATE TABLE "cases_input" ( "id" integer NOT NULL PRIMARY KEY, "details" varchar(1000) NOT NULL, "user_id" integer NOT NULL REFERENCES "auth_user" ("id"), "pub_date" datetime NOT NULL, "rating" integer NOT NULL ) ; CREATE TABLE "cases_case" ( "input_ptr_id" integer NOT NULL PRIMARY KEY REFERENCES "cases_input" ("id"), "title" varchar(200) NOT NULL, "views" integer NOT NULL ) ; CREATE TABLE "cases_argument" ( "input_ptr_id" integer NOT NULL PRIMARY KEY REFERENCES "cases_input" ("id"), "case_id" integer NOT NULL REFERENCES "cases_case" ("input_ptr_id"), "side" bool NOT NULL )

  Read the article

• Safe way for getting/finding a vertex in a graph with custom properties -> good programming practice

  - by Shadow

  Hi, I am writing a Graph-class using boost-graph-library. I use custom vertex and edge properties and a map to store/find the vertices/edges for a given property. I'm satisfied with how it works, so far. However, I have a small problem, where I'm not sure how to solve it "nicely". The class provides a method Vertex getVertex(Vertexproperties v_prop) and a method bool hasVertex(Vertexproperties v_prop) The question now is, would you judge this as good programming practice in C++? My opinion is, that I have first to check if something is available before I can get it. So, before getting a vertex with a desired property, one has to check if hasVertex() would return true for those properties. However, I would like to make getVertex() a bit more robust. ATM it will segfault when one would directly call getVertex() without prior checking if the graph has a corresponding vertex. A first idea was to return a NULL-pointer or a pointer that points past the last stored vertex. For the latter, I haven't found out how to do this. But even with this "robust" version, one would have to check for correctness after getting a vertex or one would also run into a SegFault when dereferencing that vertex-pointer for example. Therefore I am wondering if it is "ok" to let getVertex() SegFault if one does not check for availability beforehand?

  Read the article

• Safe ASCII char to replace whitespace before storing

  - by AngryWhenHungry

  My code passes a big bunch of text data to a legacy lib, which is responsible for storing it. However, it tends to remove trailing whitespace. This is a problem when I read the data back. Since I cannot change the legacy code, I thought about replacing the all spaces with some uncommon ASCII character. When I read back the text, I can replace them back. Is this a bad idea, considering that I cannot touch the legacy storage code? Which character can I use as a substitute? I was considering some char upwards of 180. There will only be spaces - no tabs or newlines - in the data. The data is alphanumeric, with special characters.

  Read the article

• Is a selector like *+* safe to use?

  - by mcmullins

  I recently came across this CSS selector while trying to find a way to easily space out major blog elements such as paragraphs and images. An example of its use would be something like this: .post *+* {margin-top: 15px;} /* or... */ .post > *+* {margin-top: 15px;} /* if you don't want the margin to apply to nested elements */ At first glance, it seemed pretty useful. So my question is: What downsides are there to using these selectors? Specifically: What's the browser support like for this? Are there any cases you wouldn't want an even margin spacing between elements in an article and if not, is it easier to declare this first and then overwrite or simply declare each element individually? Does this have performance issues since you're selecting everything twice?

  Read the article

• Visual source safe headaches - Deleting files

  - by maxp

  I will pre-empt and say we are stuck using VSS here so changing it is not an option. Anyway, one person, 'user a' is deleting a file from their project. They then do a 'get latest' on the folder and it doesn't come back, so the user assumes they have truely deleted it from the project. We have another user, 'user b', who then looks at 'pending checkins', sourcesafe will then do a scan of all the files in 'user b's project. It then wants to 're-add' all of the files user a deleted. This has caused a huge headache for the team. Any suggestions to stop this from happening again?

  Read the article

• ID generator with local static variable - thread-safe?

  - by Poseidon

  Will the following piece of code work as expected in a multi-threaded scenario? int getUniqueID() { static int ID=0; return ++ID; } It's not necessary that the IDs to be contiguous - even if it skips a value, it's fine. Can it be said that when this function returns, the value returned will be unique across all threads?

  Read the article

• are simultaneous reads of a variable thread-safe?

  - by Dasuraga

  Assuming that the variable isn't in any risk of being modified during the reads, are there any inherent problems in a variable being read by 2 or more threads at the same time?

  Read the article

• Are multiline queries sql-injection safe?

  - by acmatos

  This might be a stupid question. Or maybe my hacking skills are limited (I don't practice them at all). I have a query that looks like this: <?php $query =<<<eot SELECT table_x.field1, table_x.field2, table_y.*, table_z.field4 FROM ( SELECT ... ) as table_y LEFT JOIN table_x ON table_x.field1 = table_y.field_x LEFT JOIN table_z ON table_z.field1 = table_y.field_z WHERE table_x.field3 = '$something' AND table_z.field4 = '1' AND table_z.field5 = '2' eot; ?> I have a lot of other tests on $something before it gets used, like $something = explode(' ',$something); (which later result in a string) none of them intend to prevent injection but they make it hard for the given injection to get as is to the actual query. However, there are ways. We all know how easy it is to replace a space for something else which is still valid.. So, it's not really a problem to make a potentially harmful piece of SQL reach that $something... But is there any way to comment the rest of the original query string if it is multi-line? I can comment AND table_z.field4 = '1' using ;-- but can't comment the following AND table_z.field5 = '2' Is it possible to open a multi-line comment /* without closing it or something looked like and therefore allow the injection to ignore the multi-line query?

  Read the article

• mysql not starting

  - by Eiriks

  I have a server running on rackspace.com, it been running for about a year (collecting data for a project) and no problems. Now it seems mysql froze (could not connect either through ssh command line, remote app (sequel pro) or web (pages using the db just froze). I got a bit eager to fix this quick and rebooted the virtual server, running ubuntu 10.10. It is a small virtual LAMP server (10gig storage - I'm only using 1, 256mb ram -has not been a problem). Now after the reboot, I cannot get mysql to start again. service mysql status mysql stop/waiting I believe this just means mysql is not running. How do I get this running again? service mysql start start: Job failed to start No. Just typing 'mysql' gives: mysql ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (111) There is a .sock file in this folder, 'ls -l' gives: srwxrwxrwx 1 mysql mysql 0 2012-12-01 17:20 mysqld.sock From googleing this for a while now, I see that many talk about the logfile and my.cnf. Logs Not sure witch ones I should look at. This log-file is empty: 'var/log/mysql/error.log', so is the 'var/log/mysql.err' and 'var/log/mysql.log'. my.cnf is located in '/etc/mysql' and looks like this. Can't see anything clearly wrong with it either. # # The MySQL database server configuration file. # # You can copy this to one of: # - "/etc/mysql/my.cnf" to set global options, # - "~/.my.cnf" to set user-specific options. # # One can use all long options that the program supports. # Run program with --help to get a list of available options and with # --print-defaults to see which it would actually understand and use. # # For explanations see # http://dev.mysql.com/doc/mysql/en/server-system-variables.html # This will be passed to all mysql clients # It has been reported that passwords should be enclosed with ticks/quotes # escpecially if they contain "#" chars... # Remember to edit /etc/mysql/debian.cnf when changing the socket location. [client] port = 3306 socket = /var/run/mysqld/mysqld.sock # Here is entries for some specific programs # The following values assume you have at least 32M ram # This was formally known as [safe_mysqld]. Both versions are currently parsed. [mysqld_safe] socket = /var/run/mysqld/mysqld.sock nice = 0 [mysqld] # # * Basic Settings # # # * IMPORTANT # If you make changes to these settings and your system uses apparmor, you may # also need to also adjust /etc/apparmor.d/usr.sbin.mysqld. # user = mysql socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp skip-external-locking # # Instead of skip-networking the default is now to listen only on # localhost which is more compatible and is not less secure. bind-address = 127.0.0.1 # # * Fine Tuning # key_buffer = 16M max_allowed_packet = 16M thread_stack = 192K thread_cache_size = 8 # This replaces the startup script and checks MyISAM tables if needed # the first time they are touched myisam-recover = BACKUP #max_connections = 100 #table_cache = 64 #thread_concurrency = 10 # # * Query Cache Configuration # query_cache_limit = 1M query_cache_size = 16M # # * Logging and Replication # # Both location gets rotated by the cronjob. # Be aware that this log type is a performance killer. # As of 5.1 you can enable the log at runtime! #general_log_file = /var/log/mysql/mysql.log #general_log = 1 log_error = /var/log/mysql/error.log # Here you can see queries with especially long duration #log_slow_queries = /var/log/mysql/mysql-slow.log #long_query_time = 2 #log-queries-not-using-indexes # # The following can be used as easy to replay backup logs or for replication. # note: if you are setting up a replication slave, see README.Debian about # other settings you may need to change. #server-id = 1 #log_bin = /var/log/mysql/mysql-bin.log expire_logs_days = 10 max_binlog_size = 100M #binlog_do_db = include_database_name #binlog_ignore_db = include_database_name # # * InnoDB # # InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/. # Read the manual for more InnoDB related options. There are many! # # * Security Features # # Read the manual, too, if you want chroot! # chroot = /var/lib/mysql/ # # For generating SSL certificates I recommend the OpenSSL GUI "tinyca". # # ssl-ca=/etc/mysql/cacert.pem # ssl-cert=/etc/mysql/server-cert.pem # ssl-key=/etc/mysql/server-key.pem [mysqldump] quick quote-names max_allowed_packet = 16M [mysql] #no-auto-rehash # faster start of mysql but no tab completition [isamchk] key_buffer = 16M # # * IMPORTANT: Additional settings that can override those from this file! # The files must end with '.cnf', otherwise they'll be ignored. # !includedir /etc/mysql/conf.d/ I need the data in the database (so i'd like to avoid reinstalling), and I need it back up running again. All hint, tips and solutions are welcomed and appreciated.

  Read the article

• Best way to create SEO friendly URI string

  - by Mat Banik

  The method below allows only "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-" chars in URI strings. What better way is there to make nice SEO URI string? import org.apache.commons.lang.StringUtils; public static String safeChar(String input) { input = input.trim(); input = StringUtils.replace(input, " -", "-"); input = StringUtils.replace(input, "- ", "-"); input = StringUtils.replace(input, " - ", "-"); input = StringUtils.replaceChars(input, '\'', '-'); input = StringUtils.replaceChars(input, ' ', '-'); char[] allowed = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-".toCharArray(); char[] charArray = input.toCharArray(); StringBuilder result = new StringBuilder(); for (char c : charArray) { for (char a : allowed) { if (c == a) result.append(a); } } return result.toString(); }

  Read the article

• Need help with a PHP proxy script

  - by blabus

  I’m currently working on a small web app that allows people to search for music album covers. However, I’m having a problem getting my PHP proxy to work. Right now I’m using a simple PHP proxy script to grab the HTML from Google’s image result page, and parse it to find the first image result (I can’t use the image search API because it doesn’t offer the parameters that I need to use). I know that the PHP script works in some way, because I’ve used it to grab XML data across domains, so I also assume that since I’m trying to grab HTML that’s what’s causing the error. So anyway, here is the site where you can see it: http://www.5byfive.net/beta/index.html Just type something into the textbox, and it will come up with the error that’s returned (I’ve placed the HTML into a file so you can see what it actually looks like here: http://www.5byfive.net/beta/error.html ). Now, I’ve tried searching for info on the web, but unfortunately I basically know nothing about PHP, so I really don’t know how to fix it, and was wondering if anyone here could lend any info or help. Thanks!

  Read the article

• VB.net avoiding cross thread exception with extension method

  - by user574632

  Hello I am trying to implement a solution for updating form controls without using a delegate. I am attempting to use the 1st solution on this page: http://www.dreamincode.net/forums/blog/143/entry-2337-handling-the-dreaded-cross-thread-exception/ Imports System.ComponentModel Imports System.Runtime.CompilerServices Public Module MyInvoke <Extension()> _ Public Sub CustomInvoke(Of T As ISynchronizeInvoke)(ByVal control As T, ByVal toPerform As Action(Of T)) If control.InvokeRequired Then control.Invoke(toPerform, New Object() {control}) toPerform(control) End If End Sub End Module The site gives this as example of how to use: Label1.CustomInvoke(l => l.Text = "Hello World!") But i get 'l' is not declared error. As you can see im very new to VB or any OOP. I can get the second solution on that page to work (using delegates) but i have quite a few things to do in this thread and it seems like i would need to write a new delegate sub for each thing, which seems wasteful. What i need to do is select the 1st item from a combobox, update a textbox.text with the selected item, and pass the selected item to a function. Then wait for x seconds and start again, selecting the second item. I can get it to work in a single threaded application, but i need the interface to remain responsive. Any help greatly appreciated. EDIT: OK so changing the syntax worked for the example. However if i change it from Label1.CustomInvoke(Sub(l) l.text = "hello world!") (which worked just fine) to: Dim indexnumber As Integer = 0 ComboBox1.CustomInvoke(Sub(l) l.SelectedIndex = indexnumber) I get a cross threading error as though i didnt even use this method: Cross-thread operation not valid: Control 'ComboBox1' accessed from a thread other than the thread it was created on. So now im back to where i started? Any further help very much appreciated.

  Read the article

• value types in the vm

  - by john.rose

  value types in the vm p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times} p.p2 {margin: 0.0px 0.0px 14.0px 0.0px; font: 14.0px Times} p.p3 {margin: 0.0px 0.0px 12.0px 0.0px; font: 14.0px Times} p.p4 {margin: 0.0px 0.0px 15.0px 0.0px; font: 14.0px Times} p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Courier} p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Courier; min-height: 17.0px} p.p7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times; min-height: 18.0px} p.p8 {margin: 0.0px 0.0px 0.0px 36.0px; text-indent: -36.0px; font: 14.0px Times; min-height: 18.0px} p.p9 {margin: 0.0px 0.0px 12.0px 0.0px; font: 14.0px Times; min-height: 18.0px} p.p10 {margin: 0.0px 0.0px 12.0px 0.0px; font: 14.0px Times; color: #000000} li.li1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times} li.li7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 14.0px Times; min-height: 18.0px} span.s1 {font: 14.0px Courier} span.s2 {color: #000000} span.s3 {font: 14.0px Courier; color: #000000} ol.ol1 {list-style-type: decimal} Or, enduring values for a changing world. Introduction A value type is a data type which, generally speaking, is designed for being passed by value in and out of methods, and stored by value in data structures. The only value types which the Java language directly supports are the eight primitive types. Java indirectly and approximately supports value types, if they are implemented in terms of classes. For example, both Integer and String may be viewed as value types, especially if their usage is restricted to avoid operations appropriate to Object. In this note, we propose a definition of value types in terms of a design pattern for Java classes, accompanied by a set of usage restrictions. We also sketch the relation of such value types to tuple types (which are a JVM-level notion), and point out JVM optimizations that can apply to value types. This note is a thought experiment to extend the JVM’s performance model in support of value types. The demonstration has two phases.  Initially the extension can simply use design patterns, within the current bytecode architecture, and in today’s Java language. But if the performance model is to be realized in practice, it will probably require new JVM bytecode features, changes to the Java language, or both.  We will look at a few possibilities for these new features. An Axiom of Value In the context of the JVM, a value type is a data type equipped with construction, assignment, and equality operations, and a set of typed components, such that, whenever two variables of the value type produce equal corresponding values for their components, the values of the two variables cannot be distinguished by any JVM operation. Here are some corollaries: A value type is immutable, since otherwise a copy could be constructed and the original could be modified in one of its components, allowing the copies to be distinguished. Changing the component of a value type requires construction of a new value. The equals and hashCode operations are strictly component-wise. If a value type is represented by a JVM reference, that reference cannot be successfully synchronized on, and cannot be usefully compared for reference equality. A value type can be viewed in terms of what it doesn’t do. We can say that a value type omits all value-unsafe operations, which could violate the constraints on value types.  These operations, which are ordinarily allowed for Java object types, are pointer equality comparison (the acmp instruction), synchronization (the monitor instructions), all the wait and notify methods of class Object, and non-trivial finalize methods. The clone method is also value-unsafe, although for value types it could be treated as the identity function. Finally, and most importantly, any side effect on an object (however visible) also counts as an value-unsafe operation. A value type may have methods, but such methods must not change the components of the value. It is reasonable and useful to define methods like toString, equals, and hashCode on value types, and also methods which are specifically valuable to users of the value type. Representations of Value Value types have two natural representations in the JVM, unboxed and boxed. An unboxed value consists of the components, as simple variables. For example, the complex number x=(1+2i), in rectangular coordinate form, may be represented in unboxed form by the following pair of variables: /*Complex x = Complex.valueOf(1.0, 2.0):*/ double x_re = 1.0, x_im = 2.0; These variables might be locals, parameters, or fields. Their association as components of a single value is not defined to the JVM. Here is a sample computation which computes the norm of the difference between two complex numbers: double distance(/*Complex x:*/ double x_re, double x_im,         /*Complex y:*/ double y_re, double y_im) {     /*Complex z = x.minus(y):*/     double z_re = x_re - y_re, z_im = x_im - y_im;     /*return z.abs():*/     return Math.sqrt(z_re*z_re + z_im*z_im); } A boxed representation groups component values under a single object reference. The reference is to a ‘wrapper class’ that carries the component values in its fields. (A primitive type can naturally be equated with a trivial value type with just one component of that type. In that view, the wrapper class Integer can serve as a boxed representation of value type int.) The unboxed representation of complex numbers is practical for many uses, but it fails to cover several major use cases: return values, array elements, and generic APIs. The two components of a complex number cannot be directly returned from a Java function, since Java does not support multiple return values. The same story applies to array elements: Java has no ’array of structs’ feature. (Double-length arrays are a possible workaround for complex numbers, but not for value types with heterogeneous components.) By generic APIs I mean both those which use generic types, like Arrays.asList and those which have special case support for primitive types, like String.valueOf and PrintStream.println. Those APIs do not support unboxed values, and offer some problems to boxed values. Any ’real’ JVM type should have a story for returns, arrays, and API interoperability. The basic problem here is that value types fall between primitive types and object types. Value types are clearly more complex than primitive types, and object types are slightly too complicated. Objects are a little bit dangerous to use as value carriers, since object references can be compared for pointer equality, and can be synchronized on. Also, as many Java programmers have observed, there is often a performance cost to using wrapper objects, even on modern JVMs. Even so, wrapper classes are a good starting point for talking about value types. If there were a set of structural rules and restrictions which would prevent value-unsafe operations on value types, wrapper classes would provide a good notation for defining value types. This note attempts to define such rules and restrictions. Let’s Start Coding Now it is time to look at some real code. Here is a definition, written in Java, of a complex number value type. @ValueSafe public final class Complex implements java.io.Serializable {     // immutable component structure:     public final double re, im;     private Complex(double re, double im) {         this.re = re; this.im = im;     }     // interoperability methods:     public String toString() { return "Complex("+re+","+im+")"; }     public List<Double> asList() { return Arrays.asList(re, im); }     public boolean equals(Complex c) {         return re == c.re && im == c.im;     }     public boolean equals(@ValueSafe Object x) {         return x instanceof Complex && equals((Complex) x);     }     public int hashCode() {         return 31*Double.valueOf(re).hashCode()                 + Double.valueOf(im).hashCode();     }     // factory methods:     public static Complex valueOf(double re, double im) {         return new Complex(re, im);     }     public Complex changeRe(double re2) { return valueOf(re2, im); }     public Complex changeIm(double im2) { return valueOf(re, im2); }     public static Complex cast(@ValueSafe Object x) {         return x == null ? ZERO : (Complex) x;     }     // utility methods and constants:     public Complex plus(Complex c)  { return new Complex(re+c.re, im+c.im); }     public Complex minus(Complex c) { return new Complex(re-c.re, im-c.im); }     public double abs() { return Math.sqrt(re*re + im*im); }     public static final Complex PI = valueOf(Math.PI, 0.0);     public static final Complex ZERO = valueOf(0.0, 0.0); } This is not a minimal definition, because it includes some utility methods and other optional parts.  The essential elements are as follows: The class is marked as a value type with an annotation. The class is final, because it does not make sense to create subclasses of value types. The fields of the class are all non-private and final.  (I.e., the type is immutable and structurally transparent.) From the supertype Object, all public non-final methods are overridden. The constructor is private. Beyond these bare essentials, we can observe the following features in this example, which are likely to be typical of all value types: One or more factory methods are responsible for value creation, including a component-wise valueOf method. There are utility methods for complex arithmetic and instance creation, such as plus and changeIm. There are static utility constants, such as PI. The type is serializable, using the default mechanisms. There are methods for converting to and from dynamically typed references, such as asList and cast. The Rules In order to use value types properly, the programmer must avoid value-unsafe operations.  A helpful Java compiler should issue errors (or at least warnings) for code which provably applies value-unsafe operations, and should issue warnings for code which might be correct but does not provably avoid value-unsafe operations.  No such compilers exist today, but to simplify our account here, we will pretend that they do exist. A value-safe type is any class, interface, or type parameter marked with the @ValueSafe annotation, or any subtype of a value-safe type.  If a value-safe class is marked final, it is in fact a value type.  All other value-safe classes must be abstract.  The non-static fields of a value class must be non-public and final, and all its constructors must be private. Under the above rules, a standard interface could be helpful to define value types like Complex.  Here is an example: @ValueSafe public interface ValueType extends java.io.Serializable {     // All methods listed here must get redefined.     // Definitions must be value-safe, which means     // they may depend on component values only.     List<? extends Object> asList();     int hashCode();     boolean equals(@ValueSafe Object c);     String toString(); } //@ValueSafe inherited from supertype: public final class Complex implements ValueType { … The main advantage of such a conventional interface is that (unlike an annotation) it is reified in the runtime type system.  It could appear as an element type or parameter bound, for facilities which are designed to work on value types only.  More broadly, it might assist the JVM to perform dynamic enforcement of the rules for value types. Besides types, the annotation @ValueSafe can mark fields, parameters, local variables, and methods.  (This is redundant when the type is also value-safe, but may be useful when the type is Object or another supertype of a value type.)  Working forward from these annotations, an expression E is defined as value-safe if it satisfies one or more of the following: The type of E is a value-safe type. E names a field, parameter, or local variable whose declaration is marked @ValueSafe. E is a call to a method whose declaration is marked @ValueSafe. E is an assignment to a value-safe variable, field reference, or array reference. E is a cast to a value-safe type from a value-safe expression. E is a conditional expression E0 ? E1 : E2, and both E1 and E2 are value-safe. Assignments to value-safe expressions and initializations of value-safe names must take their values from value-safe expressions. A value-safe expression may not be the subject of a value-unsafe operation.  In particular, it cannot be synchronized on, nor can it be compared with the “==” operator, not even with a null or with another value-safe type. In a program where all of these rules are followed, no value-type value will be subject to a value-unsafe operation.  Thus, the prime axiom of value types will be satisfied, that no two value type will be distinguishable as long as their component values are equal. More Code To illustrate these rules, here are some usage examples for Complex: Complex pi = Complex.valueOf(Math.PI, 0); Complex zero = pi.changeRe(0);  //zero = pi; zero.re = 0; ValueType vtype = pi; @SuppressWarnings("value-unsafe")   Object obj = pi; @ValueSafe Object obj2 = pi; obj2 = new Object();  // ok List<Complex> clist = new ArrayList<Complex>(); clist.add(pi);  // (ok assuming List.add param is @ValueSafe) List<ValueType> vlist = new ArrayList<ValueType>(); vlist.add(pi);  // (ok) List<Object> olist = new ArrayList<Object>(); olist.add(pi);  // warning: "value-unsafe" boolean z = pi.equals(zero); boolean z1 = (pi == zero);  // error: reference comparison on value type boolean z2 = (pi == null);  // error: reference comparison on value type boolean z3 = (pi == obj2);  // error: reference comparison on value type synchronized (pi) { }  // error: synch of value, unpredictable result synchronized (obj2) { }  // unpredictable result Complex qq = pi; qq = null;  // possible NPE; warning: “null-unsafe" qq = (Complex) obj;  // warning: “null-unsafe" qq = Complex.cast(obj);  // OK @SuppressWarnings("null-unsafe")   Complex empty = null;  // possible NPE qq = empty;  // possible NPE (null pollution) The Payoffs It follows from this that either the JVM or the java compiler can replace boxed value-type values with unboxed ones, without affecting normal computations.  Fields and variables of value types can be split into their unboxed components.  Non-static methods on value types can be transformed into static methods which take the components as value parameters. Some common questions arise around this point in any discussion of value types. Why burden the programmer with all these extra rules?  Why not detect programs automagically and perform unboxing transparently?  The answer is that it is easy to break the rules accidently unless they are agreed to by the programmer and enforced.  Automatic unboxing optimizations are tantalizing but (so far) unreachable ideal.  In the current state of the art, it is possible exhibit benchmarks in which automatic unboxing provides the desired effects, but it is not possible to provide a JVM with a performance model that assures the programmer when unboxing will occur.  This is why I’m writing this note, to enlist help from, and provide assurances to, the programmer.  Basically, I’m shooting for a good set of user-supplied “pragmas” to frame the desired optimization. Again, the important thing is that the unboxing must be done reliably, or else programmers will have no reason to work with the extra complexity of the value-safety rules.  There must be a reasonably stable performance model, wherein using a value type has approximately the same performance characteristics as writing the unboxed components as separate Java variables. There are some rough corners to the present scheme.  Since Java fields and array elements are initialized to null, value-type computations which incorporate uninitialized variables can produce null pointer exceptions.  One workaround for this is to require such variables to be null-tested, and the result replaced with a suitable all-zero value of the value type.  That is what the “cast” method does above. Generically typed APIs like List<T> will continue to manipulate boxed values always, at least until we figure out how to do reification of generic type instances.  Use of such APIs will elicit warnings until their type parameters (and/or relevant members) are annotated or typed as value-safe.  Retrofitting List<T> is likely to expose flaws in the present scheme, which we will need to engineer around.  Here are a couple of first approaches: public interface java.util.List<@ValueSafe T> extends Collection<T> { … public interface java.util.List<T extends Object|ValueType> extends Collection<T> { … (The second approach would require disjunctive types, in which value-safety is “contagious” from the constituent types.) With more transformations, the return value types of methods can also be unboxed.  This may require significant bytecode-level transformations, and would work best in the presence of a bytecode representation for multiple value groups, which I have proposed elsewhere under the title “Tuples in the VM”. But for starters, the JVM can apply this transformation under the covers, to internally compiled methods.  This would give a way to express multiple return values and structured return values, which is a significant pain-point for Java programmers, especially those who work with low-level structure types favored by modern vector and graphics processors.  The lack of multiple return values has a strong distorting effect on many Java APIs. Even if the JVM fails to unbox a value, there is still potential benefit to the value type.  Clustered computing systems something have copy operations (serialization or something similar) which apply implicitly to command operands.  When copying JVM objects, it is extremely helpful to know when an object’s identity is important or not.  If an object reference is a copied operand, the system may have to create a proxy handle which points back to the original object, so that side effects are visible.  Proxies must be managed carefully, and this can be expensive.  On the other hand, value types are exactly those types which a JVM can “copy and forget” with no downside. Array types are crucial to bulk data interfaces.  (As data sizes and rates increase, bulk data becomes more important than scalar data, so arrays are definitely accompanying us into the future of computing.)  Value types are very helpful for adding structure to bulk data, so a successful value type mechanism will make it easier for us to express richer forms of bulk data. Unboxing arrays (i.e., arrays containing unboxed values) will provide better cache and memory density, and more direct data movement within clustered or heterogeneous computing systems.  They require the deepest transformations, relative to today’s JVM.  There is an impedance mismatch between value-type arrays and Java’s covariant array typing, so compromises will need to be struck with existing Java semantics.  It is probably worth the effort, since arrays of unboxed value types are inherently more memory-efficient than standard Java arrays, which rely on dependent pointer chains. It may be sufficient to extend the “value-safe” concept to array declarations, and allow low-level transformations to change value-safe array declarations from the standard boxed form into an unboxed tuple-based form.  Such value-safe arrays would not be convertible to Object[] arrays.  Certain connection points, such as Arrays.copyOf and System.arraycopy might need additional input/output combinations, to allow smooth conversion between arrays with boxed and unboxed elements. Alternatively, the correct solution may have to wait until we have enough reification of generic types, and enough operator overloading, to enable an overhaul of Java arrays. Implicit Method Definitions The example of class Complex above may be unattractively complex.  I believe most or all of the elements of the example class are required by the logic of value types. If this is true, a programmer who writes a value type will have to write lots of error-prone boilerplate code.  On the other hand, I think nearly all of the code (except for the domain-specific parts like plus and minus) can be implicitly generated. Java has a rule for implicitly defining a class’s constructor, if no it defines no constructors explicitly.  Likewise, there are rules for providing default access modifiers for interface members.  Because of the highly regular structure of value types, it might be reasonable to perform similar implicit transformations on value types.  Here’s an example of a “highly implicit” definition of a complex number type: public class Complex implements ValueType {  // implicitly final     public double re, im;  // implicitly public final     //implicit methods are defined elementwise from te fields:     //  toString, asList, equals(2), hashCode, valueOf, cast     //optionally, explicit methods (plus, abs, etc.) would go here } In other words, with the right defaults, a simple value type definition can be a one-liner.  The observant reader will have noticed the similarities (and suitable differences) between the explicit methods above and the corresponding methods for List<T>. Another way to abbreviate such a class would be to make an annotation the primary trigger of the functionality, and to add the interface(s) implicitly: public @ValueType class Complex { … // implicitly final, implements ValueType (But to me it seems better to communicate the “magic” via an interface, even if it is rooted in an annotation.) Implicitly Defined Value Types So far we have been working with nominal value types, which is to say that the sequence of typed components is associated with a name and additional methods that convey the intention of the programmer.  A simple ordered pair of floating point numbers can be variously interpreted as (to name a few possibilities) a rectangular or polar complex number or Cartesian point.  The name and the methods convey the intended meaning. But what if we need a truly simple ordered pair of floating point numbers, without any further conceptual baggage?  Perhaps we are writing a method (like “divideAndRemainder”) which naturally returns a pair of numbers instead of a single number.  Wrapping the pair of numbers in a nominal type (like “QuotientAndRemainder”) makes as little sense as wrapping a single return value in a nominal type (like “Quotient”).  What we need here are structural value types commonly known as tuples. For the present discussion, let us assign a conventional, JVM-friendly name to tuples, roughly as follows: public class java.lang.tuple.$DD extends java.lang.tuple.Tuple {      double $1, $2; } Here the component names are fixed and all the required methods are defined implicitly.  The supertype is an abstract class which has suitable shared declarations.  The name itself mentions a JVM-style method parameter descriptor, which may be “cracked” to determine the number and types of the component fields. The odd thing about such a tuple type (and structural types in general) is it must be instantiated lazily, in response to linkage requests from one or more classes that need it.  The JVM and/or its class loaders must be prepared to spin a tuple type on demand, given a simple name reference, $xyz, where the xyz is cracked into a series of component types.  (Specifics of naming and name mangling need some tasteful engineering.) Tuples also seem to demand, even more than nominal types, some support from the language.  (This is probably because notations for non-nominal types work best as combinations of punctuation and type names, rather than named constructors like Function3 or Tuple2.)  At a minimum, languages with tuples usually (I think) have some sort of simple bracket notation for creating tuples, and a corresponding pattern-matching syntax (or “destructuring bind”) for taking tuples apart, at least when they are parameter lists.  Designing such a syntax is no simple thing, because it ought to play well with nominal value types, and also with pre-existing Java features, such as method parameter lists, implicit conversions, generic types, and reflection.  That is a task for another day. Other Use Cases Besides complex numbers and simple tuples there are many use cases for value types.  Many tuple-like types have natural value-type representations. These include rational numbers, point locations and pixel colors, and various kinds of dates and addresses. Other types have a variable-length ‘tail’ of internal values. The most common example of this is String, which is (mathematically) a sequence of UTF-16 character values. Similarly, bit vectors, multiple-precision numbers, and polynomials are composed of sequences of values. Such types include, in their representation, a reference to a variable-sized data structure (often an array) which (somehow) represents the sequence of values. The value type may also include ’header’ information. Variable-sized values often have a length distribution which favors short lengths. In that case, the design of the value type can make the first few values in the sequence be direct ’header’ fields of the value type. In the common case where the header is enough to represent the whole value, the tail can be a shared null value, or even just a null reference. Note that the tail need not be an immutable object, as long as the header type encapsulates it well enough. This is the case with String, where the tail is a mutable (but never mutated) character array. Field types and their order must be a globally visible part of the API.  The structure of the value type must be transparent enough to have a globally consistent unboxed representation, so that all callers and callees agree about the type and order of components  that appear as parameters, return types, and array elements.  This is a trade-off between efficiency and encapsulation, which is forced on us when we remove an indirection enjoyed by boxed representations.  A JVM-only transformation would not care about such visibility, but a bytecode transformation would need to take care that (say) the components of complex numbers would not get swapped after a redefinition of Complex and a partial recompile.  Perhaps constant pool references to value types need to declare the field order as assumed by each API user. This brings up the delicate status of private fields in a value type.  It must always be possible to load, store, and copy value types as coordinated groups, and the JVM performs those movements by moving individual scalar values between locals and stack.  If a component field is not public, what is to prevent hostile code from plucking it out of the tuple using a rogue aload or astore instruction?  Nothing but the verifier, so we may need to give it more smarts, so that it treats value types as inseparable groups of stack slots or locals (something like long or double). My initial thought was to make the fields always public, which would make the security problem moot.  But public is not always the right answer; consider the case of String, where the underlying mutable character array must be encapsulated to prevent security holes.  I believe we can win back both sides of the tradeoff, by training the verifier never to split up the components in an unboxed value.  Just as the verifier encapsulates the two halves of a 64-bit primitive, it can encapsulate the the header and body of an unboxed String, so that no code other than that of class String itself can take apart the values. Similar to String, we could build an efficient multi-precision decimal type along these lines: public final class DecimalValue extends ValueType {     protected final long header;     protected private final BigInteger digits;     public DecimalValue valueOf(int value, int scale) {         assert(scale >= 0);         return new DecimalValue(((long)value << 32) + scale, null);     }     public DecimalValue valueOf(long value, int scale) {         if (value == (int) value)             return valueOf((int)value, scale);         return new DecimalValue(-scale, new BigInteger(value));     } } Values of this type would be passed between methods as two machine words. Small values (those with a significand which fits into 32 bits) would be represented without any heap data at all, unless the DecimalValue itself were boxed. (Note the tension between encapsulation and unboxing in this case.  It would be better if the header and digits fields were private, but depending on where the unboxing information must “leak”, it is probably safer to make a public revelation of the internal structure.) Note that, although an array of Complex can be faked with a double-length array of double, there is no easy way to fake an array of unboxed DecimalValues.  (Either an array of boxed values or a transposed pair of homogeneous arrays would be reasonable fallbacks, in a current JVM.)  Getting the full benefit of unboxing and arrays will require some new JVM magic. Although the JVM emphasizes portability, system dependent code will benefit from using machine-level types larger than 64 bits.  For example, the back end of a linear algebra package might benefit from value types like Float4 which map to stock vector types.  This is probably only worthwhile if the unboxing arrays can be packed with such values. More Daydreams A more finely-divided design for dynamic enforcement of value safety could feature separate marker interfaces for each invariant.  An empty marker interface Unsynchronizable could cause suitable exceptions for monitor instructions on objects in marked classes.  More radically, a Interchangeable marker interface could cause JVM primitives that are sensitive to object identity to raise exceptions; the strangest result would be that the acmp instruction would have to be specified as raising an exception. @ValueSafe public interface ValueType extends java.io.Serializable,         Unsynchronizable, Interchangeable { … public class Complex implements ValueType {     // inherits Serializable, Unsynchronizable, Interchangeable, @ValueSafe     … It seems possible that Integer and the other wrapper types could be retro-fitted as value-safe types.  This is a major change, since wrapper objects would be unsynchronizable and their references interchangeable.  It is likely that code which violates value-safety for wrapper types exists but is uncommon.  It is less plausible to retro-fit String, since the prominent operation String.intern is often used with value-unsafe code. We should also reconsider the distinction between boxed and unboxed values in code.  The design presented above obscures that distinction.  As another thought experiment, we could imagine making a first class distinction in the type system between boxed and unboxed representations.  Since only primitive types are named with a lower-case initial letter, we could define that the capitalized version of a value type name always refers to the boxed representation, while the initial lower-case variant always refers to boxed.  For example: complex pi = complex.valueOf(Math.PI, 0); Complex boxPi = pi;  // convert to boxed myList.add(boxPi); complex z = myList.get(0);  // unbox Such a convention could perhaps absorb the current difference between int and Integer, double and Double. It might also allow the programmer to express a helpful distinction among array types. As said above, array types are crucial to bulk data interfaces, but are limited in the JVM.  Extending arrays beyond the present limitations is worth thinking about; for example, the Maxine JVM implementation has a hybrid object/array type.  Something like this which can also accommodate value type components seems worthwhile.  On the other hand, does it make sense for value types to contain short arrays?  And why should random-access arrays be the end of our design process, when bulk data is often sequentially accessed, and it might make sense to have heterogeneous streams of data as the natural “jumbo” data structure.  These considerations must wait for another day and another note. More Work It seems to me that a good sequence for introducing such value types would be as follows: Add the value-safety restrictions to an experimental version of javac. Code some sample applications with value types, including Complex and DecimalValue. Create an experimental JVM which internally unboxes value types but does not require new bytecodes to do so.  Ensure the feasibility of the performance model for the sample applications. Add tuple-like bytecodes (with or without generic type reification) to a major revision of the JVM, and teach the Java compiler to switch in the new bytecodes without code changes. A staggered roll-out like this would decouple language changes from bytecode changes, which is always a convenient thing. A similar investigation should be applied (concurrently) to array types.  In this case, it seems to me that the starting point is in the JVM: Add an experimental unboxing array data structure to a production JVM, perhaps along the lines of Maxine hybrids.  No bytecode or language support is required at first; everything can be done with encapsulated unsafe operations and/or method handles. Create an experimental JVM which internally unboxes value types but does not require new bytecodes to do so.  Ensure the feasibility of the performance model for the sample applications. Add tuple-like bytecodes (with or without generic type reification) to a major revision of the JVM, and teach the Java compiler to switch in the new bytecodes without code changes. That’s enough musing me for now.  Back to work!

  Read the article

• How do I allow mysqld to use more than 24.9% of my cpu?

  - by Joseph Yancey

  I have a Web server running on RHEL that is running Apache and MySQL. It has a Quad core 3.2Ghz Xeon CPU and 8 Gigs of RAM Most of the time, we don't have any issues at all. Our web application is very database intensive. When our usage gets pretty heavy MySQL will peg out at using 24.9% of the cpu. Most of the time, it hangs around below 5%. I have speculated that it is only using one core of the CPU and it is pegging out that core but TOP shows me in the cpu column that mysqld changes cores even while the usage stays at 24.9%. When it does this MySQL gets painfully slow as it is queuing up queries Is there some magic configuration that will tell mysql to use more cpu when it needs to? Also, any other advice on my configuration would be helpful. We run two applications on this server. One that runs Innodb but doesn't get much usage (it has been replaced by the other app), and one that runs MyIsam and gets lots of use. Overall, our whole mysql data directory is something like 13Gigs if that matters at all. Here is my config: [root@ProductionLinux root]# cat /etc/my.cnf [mysqld] server-id = 71 log-bin = /var/log/mysql/mysql-bin.log binlog-do-db = oldapplication binlog-do-db = newapplication binlog-do-db = support thread_cache_size = 30 key_buffer_size = 256M table_cache = 256 sort_buffer_size = 4M read_buffer_size = 1M skip-name-resolve innodb_data_home_dir = /usr/local/mysql/data/ innodb_data_file_path = InnoDB:100M:autoextend set-variable = innodb_buffer_pool_size=70M set-variable = innodb_additional_mem_pool_size=10M set-variable = max_connections=500 innodb_log_group_home_dir = /usr/local/mysql/data innodb_log_arch_dir = /usr/local/mysql/data set-variable = innodb_log_file_size=20M set-variable = innodb_log_buffer_size=8M innodb_flush_log_at_trx_commit = 1 log-queries-not-using-indexes log-error = /var/log/mysql/mysql-error.log mysql show variables; +---------------------------------+-----------------------------------------------------------------------------+ | Variable_name | Value | +---------------------------------+-----------------------------------------------------------------------------+ | auto_increment_increment | 1 | | auto_increment_offset | 1 | | automatic_sp_privileges | ON | | back_log | 50 | | basedir | /usr/local/mysql-standard-5.0.18-linux-x86_64-glibc23/ | | binlog_cache_size | 32768 | | bulk_insert_buffer_size | 8388608 | | character_set_client | latin1 | | character_set_connection | latin1 | | character_set_database | latin1 | | character_set_results | latin1 | | character_set_server | latin1 | | character_set_system | utf8 | | character_sets_dir | /usr/local/mysql-standard-5.0.18-linux-x86_64-glibc23/share/mysql/charsets/ | | collation_connection | latin1_swedish_ci | | collation_database | latin1_swedish_ci | | collation_server | latin1_swedish_ci | | completion_type | 0 | | concurrent_insert | 1 | | connect_timeout | 5 | | datadir | /usr/local/mysql/data/ | | date_format | %Y-%m-%d | | datetime_format | %Y-%m-%d %H:%i:%s | | default_week_format | 0 | | delay_key_write | ON | | delayed_insert_limit | 100 | | delayed_insert_timeout | 300 | | delayed_queue_size | 1000 | | div_precision_increment | 4 | | engine_condition_pushdown | OFF | | expire_logs_days | 0 | | flush | OFF | | flush_time | 0 | | | ft_max_word_len | 84 | | ft_min_word_len | 4 | | ft_query_expansion_limit | 20 | | ft_stopword_file | (built-in) | | group_concat_max_len | 1024 | | have_archive | YES | | have_bdb | NO | | have_blackhole_engine | NO | | have_compress | YES | | have_crypt | YES | | have_csv | NO | | have_example_engine | NO | | have_federated_engine | NO | | have_geometry | YES | | have_innodb | YES | | have_isam | NO | | have_ndbcluster | NO | | have_openssl | NO | | have_query_cache | YES | | have_raid | NO | | have_rtree_keys | YES | | have_symlink | YES | | init_connect | | | init_file | | | init_slave | | | innodb_additional_mem_pool_size | 10485760 | | innodb_autoextend_increment | 8 | | innodb_buffer_pool_awe_mem_mb | 0 | | innodb_buffer_pool_size | 73400320 | | innodb_checksums | ON | | innodb_commit_concurrency | 0 | | innodb_concurrency_tickets | 500 | | innodb_data_file_path | InnoDB:100M:autoextend | | innodb_data_home_dir | /usr/local/mysql/data/ | | innodb_doublewrite | ON | | innodb_fast_shutdown | 1 | | innodb_file_io_threads | 4 | | innodb_file_per_table | OFF | | innodb_flush_log_at_trx_commit | 1 | | innodb_flush_method | | | innodb_force_recovery | 0 | | innodb_lock_wait_timeout | 50 | | innodb_locks_unsafe_for_binlog | OFF | | innodb_log_arch_dir | /usr/local/mysql/data | | innodb_log_archive | OFF | | innodb_log_buffer_size | 8388608 | | innodb_log_file_size | 20971520 | | innodb_log_files_in_group | 2 | | innodb_log_group_home_dir | /usr/local/mysql/data | | innodb_max_dirty_pages_pct | 90 | | innodb_max_purge_lag | 0 | | innodb_mirrored_log_groups | 1 | | innodb_open_files | 300 | | innodb_support_xa | ON | | innodb_sync_spin_loops | 20 | | innodb_table_locks | ON | | innodb_thread_concurrency | 20 | | innodb_thread_sleep_delay | 10000 | | interactive_timeout | 28800 | | join_buffer_size | 131072 | | key_buffer_size | 268435456 | | key_cache_age_threshold | 300 | | key_cache_block_size | 1024 | | key_cache_division_limit | 100 | | language | /usr/local/mysql-standard-5.0.18-linux-x86_64-glibc23/share/mysql/english/ | | large_files_support | ON | | large_page_size | 0 | | large_pages | OFF | | license | GPL | | local_infile | ON | | locked_in_memory | OFF | | log | OFF | | log_bin | ON | | log_bin_trust_function_creators | OFF | | log_error | /var/log/mysql/mysql-error.log | | log_slave_updates | OFF | | log_slow_queries | OFF | | log_warnings | 1 | | long_query_time | 10 | | low_priority_updates | OFF | | lower_case_file_system | OFF | | lower_case_table_names | 0 | | max_allowed_packet | 1048576 | | max_binlog_cache_size | 18446744073709551615 | | max_binlog_size | 1073741824 | | max_connect_errors | 10 | | max_connections | 500 | | max_delayed_threads | 20 | | max_error_count | 64 | | max_heap_table_size | 16777216 | | max_insert_delayed_threads | 20 | | max_join_size | 18446744073709551615 | | max_length_for_sort_data | 1024 | | max_relay_log_size | 0 | | max_seeks_for_key | 18446744073709551615 | | max_sort_length | 1024 | | max_sp_recursion_depth | 0 | | max_tmp_tables | 32 | | max_user_connections | 0 | | max_write_lock_count | 18446744073709551615 | | multi_range_count | 256 | | myisam_data_pointer_size | 6 | | myisam_max_sort_file_size | 9223372036854775807 | | myisam_recover_options | OFF | | myisam_repair_threads | 1 | | myisam_sort_buffer_size | 8388608 | | myisam_stats_method | nulls_unequal | | net_buffer_length | 16384 | | net_read_timeout | 30 | | net_retry_count | 10 | | net_write_timeout | 60 | | new | OFF | | old_passwords | OFF | | open_files_limit | 2510 | | optimizer_prune_level | 1 | | optimizer_search_depth | 62 | | pid_file | /usr/local/mysql/data/ProductionLinux.pid | | port | 3306 | | preload_buffer_size | 32768 | | protocol_version | 10 | | query_alloc_block_size | 8192 | | query_cache_limit | 1048576 | | query_cache_min_res_unit | 4096 | | query_cache_size | 0 | | query_cache_type | ON | | query_cache_wlock_invalidate | OFF | | query_prealloc_size | 8192 | | range_alloc_block_size | 2048 | | read_buffer_size | 1044480 | | read_only | OFF | | read_rnd_buffer_size | 262144 | | relay_log_purge | ON | | relay_log_space_limit | 0 | | rpl_recovery_rank | 0 | | secure_auth | OFF | | server_id | 71 | | skip_external_locking | ON | | skip_networking | OFF | | skip_show_database | OFF | | slave_compressed_protocol | OFF | | slave_load_tmpdir | /tmp/ | | slave_net_timeout | 3600 | | slave_skip_errors | OFF | | slave_transaction_retries | 10 | | slow_launch_time | 2 | | socket | /tmp/mysql.sock | | sort_buffer_size | 4194296 | | sql_mode | | | sql_notes | ON | | sql_warnings | ON | | storage_engine | MyISAM | | sync_binlog | 0 | | sync_frm | ON | | sync_replication | 0 | | sync_replication_slave_id | 0 | | sync_replication_timeout | 10 | | system_time_zone | CST | | table_cache | 256 | | table_lock_wait_timeout | 50 | | table_type | MyISAM | | thread_cache_size | 30 | | thread_stack | 262144 | | time_format | %H:%i:%s | | time_zone | SYSTEM | | timed_mutexes | OFF | | tmp_table_size | 33554432 | | tmpdir | | | transaction_alloc_block_size | 8192 | | transaction_prealloc_size | 4096 | | tx_isolation | REPEATABLE-READ | | updatable_views_with_limit | YES | | version | 5.0.18-standard-log | | version_comment | MySQL Community Edition - Standard (GPL) | | version_compile_machine | x86_64 | | version_compile_os | unknown-linux-gnu | | wait_timeout | 28800 | +---------------------------------+-----------------------------------------------------------------------------+ 210 rows in set (0.00 sec)

  Read the article

• Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

  - by jasonspiro

  A client of my IT-consulting service owns a web-development shop. He's been having problems with a Slackware 12.0 server running MySQL 5.0.67. The machine was set up by the client's sysadmin, who left on bad terms. My client no longer employs a sysadmin. As far as I can tell, the only copy of MySQL that's installed is the one described in /var/log/packages/mysql-5.0.67-i486-1: PACKAGE NAME: mysql-5.0.67-i486-1 COMPRESSED PACKAGE SIZE: 16828 K UNCOMPRESSED PACKAGE SIZE: 33840 K PACKAGE LOCATION: /var/slapt-get/archives/./slackware/ap/mysql-5.0.67-i486-1.tgz PACKAGE DESCRIPTION: mysql: mysql (SQL-based relational database server) mysql: mysql: MySQL is a fast, multi-threaded, multi-user, and robust SQL mysql: (Structured Query Language) database server. It comes with a nice API mysql: which makes it easy to integrate into other applications. mysql: mysql: The home page for MySQL is http://www.mysql.com/ mysql: mysql: mysql: mysql: FILE LIST: ./ var/ var/lib/ var/lib/mysql/ var/run/ var/run/mysql/ install/ install/doinst.sh install/slack-desc usr/ usr/include/ usr/include/mysql/ usr/include/mysql/my_alloc.h usr/include/mysql/sql_common.h usr/include/mysql/my_dbug.h usr/include/mysql/errmsg.h usr/include/mysql/my_pthread.h usr/include/mysql/my_list.h usr/include/mysql/mysql.h usr/include/mysql/sslopt-vars.h usr/include/mysql/my_config.h usr/include/mysql/mysql_com.h usr/include/mysql/m_string.h usr/include/mysql/sslopt-case.h usr/include/mysql/my_xml.h usr/include/mysql/sql_state.h usr/include/mysql/my_global.h usr/include/mysql/my_sys.h usr/include/mysql/mysqld_ername.h usr/include/mysql/mysqld_error.h usr/include/mysql/sslopt-longopts.h usr/include/mysql/keycache.h usr/include/mysql/my_net.h usr/include/mysql/mysql_version.h usr/include/mysql/my_no_pthread.h usr/include/mysql/decimal.h usr/include/mysql/readline.h usr/include/mysql/my_attribute.h usr/include/mysql/typelib.h usr/include/mysql/my_dir.h usr/include/mysql/raid.h usr/include/mysql/m_ctype.h usr/include/mysql/mysql_embed.h usr/include/mysql/mysql_time.h usr/include/mysql/my_getopt.h usr/lib/ usr/lib/mysql/ usr/lib/mysql/libmysqlclient_r.so.15.0.0 usr/lib/mysql/libmysqlclient_r.la usr/lib/mysql/libmyisammrg.a usr/lib/mysql/libmystrings.a usr/lib/mysql/libmyisam.a usr/lib/mysql/libmysqlclient.so.15.0.0 usr/lib/mysql/libmysqlclient_r.a usr/lib/mysql/libmysqlclient.a usr/lib/mysql/libheap.a usr/lib/mysql/libvio.a usr/lib/mysql/libmysqlclient.la usr/lib/mysql/libmysys.a usr/lib/mysql/libdbug.a usr/bin/ usr/bin/comp_err usr/bin/my_print_defaults usr/bin/resolve_stack_dump usr/bin/msql2mysql usr/bin/mysqltestmanager-pwgen usr/bin/myisampack usr/bin/replace usr/bin/mysqld_multi usr/bin/mysqlaccess usr/bin/mysql_install_db usr/bin/innochecksum usr/bin/myisam_ftdump usr/bin/mysqlcheck usr/bin/mysqltest usr/bin/mysql_upgrade_shell usr/bin/mysql_secure_installation usr/bin/mysql_fix_extensions usr/bin/mysqld_safe usr/bin/mysql_explain_log usr/bin/mysqlimport usr/bin/myisamlog usr/bin/mysql_tzinfo_to_sql usr/bin/mysql_upgrade usr/bin/mysqltestmanager usr/bin/mysql_fix_privilege_tables usr/bin/mysql_find_rows usr/bin/mysql_convert_table_format usr/bin/mysqltestmanagerc usr/bin/mysqlhotcopy usr/bin/mysqldump usr/bin/mysqlshow usr/bin/mysqlbug usr/bin/mysql_config usr/bin/mysqldumpslow usr/bin/mysql_waitpid usr/bin/mysqlbinlog usr/bin/mysql_client_test usr/bin/perror usr/bin/mysql usr/bin/myisamchk usr/bin/mysql_setpermission usr/bin/mysqladmin usr/bin/mysql_zap usr/bin/mysql_tableinfo usr/bin/resolveip usr/share/ usr/share/mysql/ usr/share/mysql/errmsg.txt usr/share/mysql/swedish/ usr/share/mysql/swedish/errmsg.sys usr/share/mysql/mysql_system_tables_data.sql usr/share/mysql/mysql.server usr/share/mysql/hungarian/ usr/share/mysql/hungarian/errmsg.sys usr/share/mysql/norwegian/ usr/share/mysql/norwegian/errmsg.sys usr/share/mysql/slovak/ usr/share/mysql/slovak/errmsg.sys usr/share/mysql/spanish/ usr/share/mysql/spanish/errmsg.sys usr/share/mysql/polish/ usr/share/mysql/polish/errmsg.sys usr/share/mysql/ukrainian/ usr/share/mysql/ukrainian/errmsg.sys usr/share/mysql/danish/ usr/share/mysql/danish/errmsg.sys usr/share/mysql/romanian/ usr/share/mysql/romanian/errmsg.sys usr/share/mysql/english/ usr/share/mysql/english/errmsg.sys usr/share/mysql/charsets/ usr/share/mysql/charsets/latin2.xml usr/share/mysql/charsets/greek.xml usr/share/mysql/charsets/koi8r.xml usr/share/mysql/charsets/latin1.xml usr/share/mysql/charsets/cp866.xml usr/share/mysql/charsets/geostd8.xml usr/share/mysql/charsets/cp1250.xml usr/share/mysql/charsets/koi8u.xml usr/share/mysql/charsets/cp852.xml usr/share/mysql/charsets/hebrew.xml usr/share/mysql/charsets/latin7.xml usr/share/mysql/charsets/README usr/share/mysql/charsets/ascii.xml usr/share/mysql/charsets/cp1251.xml usr/share/mysql/charsets/macce.xml usr/share/mysql/charsets/latin5.xml usr/share/mysql/charsets/Index.xml usr/share/mysql/charsets/macroman.xml usr/share/mysql/charsets/cp1256.xml usr/share/mysql/charsets/keybcs2.xml usr/share/mysql/charsets/swe7.xml usr/share/mysql/charsets/armscii8.xml usr/share/mysql/charsets/dec8.xml usr/share/mysql/charsets/cp1257.xml usr/share/mysql/charsets/hp8.xml usr/share/mysql/charsets/cp850.xml usr/share/mysql/korean/ usr/share/mysql/korean/errmsg.sys usr/share/mysql/german/ usr/share/mysql/german/errmsg.sys usr/share/mysql/mi_test_all.res usr/share/mysql/greek/ usr/share/mysql/greek/errmsg.sys usr/share/mysql/french/ usr/share/mysql/french/errmsg.sys usr/share/mysql/mysql_fix_privilege_tables.sql usr/share/mysql/dutch/ usr/share/mysql/dutch/errmsg.sys usr/share/mysql/serbian/ usr/share/mysql/serbian/errmsg.sys usr/share/mysql/mysql_system_tables.sql usr/share/mysql/my-huge.cnf usr/share/mysql/portuguese/ usr/share/mysql/portuguese/errmsg.sys usr/share/mysql/japanese/ usr/share/mysql/japanese/errmsg.sys usr/share/mysql/mysql_test_data_timezone.sql usr/share/mysql/russian/ usr/share/mysql/russian/errmsg.sys usr/share/mysql/czech/ usr/share/mysql/czech/errmsg.sys usr/share/mysql/fill_help_tables.sql usr/share/mysql/estonian/ usr/share/mysql/estonian/errmsg.sys usr/share/mysql/my-medium.cnf usr/share/mysql/norwegian-ny/ usr/share/mysql/norwegian-ny/errmsg.sys usr/share/mysql/my-small.cnf usr/share/mysql/mysql-log-rotate usr/share/mysql/italian/ usr/share/mysql/italian/errmsg.sys usr/share/mysql/my-large.cnf usr/share/mysql/ndb-config-2-node.ini usr/share/mysql/binary-configure usr/share/mysql/mi_test_all usr/share/mysql/mysqld_multi.server usr/share/mysql/my-innodb-heavy-4G.cnf usr/doc/ usr/doc/mysql-5.0.67/ usr/doc/mysql-5.0.67/README usr/doc/mysql-5.0.67/Docs/ usr/doc/mysql-5.0.67/Docs/INSTALL-BINARY usr/doc/mysql-5.0.67/COPYING usr/info/ usr/info/mysql.info.gz usr/libexec/ usr/libexec/mysqld usr/libexec/mysqlmanager usr/man/ usr/man/man8/ usr/man/man8/mysqlmanager.8.gz usr/man/man8/mysqld.8.gz usr/man/man1/ usr/man/man1/mysql_zap.1.gz usr/man/man1/mysql_setpermission.1.gz usr/man/man1/mysql_tzinfo_to_sql.1.gz usr/man/man1/msql2mysql.1.gz usr/man/man1/mysql_tableinfo.1.gz usr/man/man1/mysql_explain_log.1.gz usr/man/man1/mysqlcheck.1.gz usr/man/man1/comp_err.1.gz usr/man/man1/my_print_defaults.1.gz usr/man/man1/mysqlbinlog.1.gz usr/man/man1/myisam_ftdump.1.gz usr/man/man1/mysql_upgrade.1.gz usr/man/man1/mysql.1.gz usr/man/man1/mysql_client_test.1.gz usr/man/man1/resolve_stack_dump.1.gz usr/man/man1/mysql_fix_extensions.1.gz usr/man/man1/mysqlmanagerc.1.gz usr/man/man1/mysql_config.1.gz usr/man/man1/mysqlshow.1.gz usr/man/man1/myisamlog.1.gz usr/man/man1/replace.1.gz usr/man/man1/mysqlmanager-pwgen.1.gz usr/man/man1/mysqltest.1.gz usr/man/man1/innochecksum.1.gz usr/man/man1/mysqladmin.1.gz usr/man/man1/perror.1.gz usr/man/man1/mysql_waitpid.1.gz usr/man/man1/mysql_convert_table_format.1.gz usr/man/man1/mysqlman.1.gz usr/man/man1/mysqlimport.1.gz usr/man/man1/mysqlbug.1.gz usr/man/man1/mysql_find_rows.1.gz usr/man/man1/myisampack.1.gz usr/man/man1/myisamchk.1.gz usr/man/man1/mysql_fix_privilege_tables.1.gz usr/man/man1/mysql-stress-test.pl.1.gz usr/man/man1/resolveip.1.gz usr/man/man1/make_win_bin_dist.1.gz usr/man/man1/mysqlhotcopy.1.gz usr/man/man1/mysqld_multi.1.gz usr/man/man1/safe_mysqld.1.gz usr/man/man1/mysql_secure_installation.1.gz usr/man/man1/mysql_install_db.1.gz usr/man/man1/mysqldump.1.gz usr/man/man1/mysql-test-run.pl.1.gz usr/man/man1/mysqld_safe.1.gz usr/man/man1/mysqlaccess.1.gz usr/man/man1/mysql.server.1.gz usr/man/man1/make_win_src_distribution.1.gz etc/ etc/rc.d/ etc/rc.d/rc.mysqld.new etc/my-huge.cnf etc/my-medium.cnf etc/my-small.cnf etc/my-large.cnf /etc/rc.d/rc.mysqld is an ordinary Slackware-type start/stop script: #!/bin/sh # Start/stop/restart mysqld. # # Copyright 2003 Patrick J. Volkerding, Concord, CA # Copyright 2003 Slackware Linux, Inc., Concord, CA # # This program comes with NO WARRANTY, to the extent permitted by law. # You may redistribute copies of this program under the terms of the # GNU General Public License. # To start MySQL automatically at boot, be sure this script is executable: # chmod 755 /etc/rc.d/rc.mysqld # Before you can run MySQL, you must have a database. To install an initial # database, do this as root: # # su - mysql # mysql_install_db # # Note that step one is becoming the mysql user. It's important to do this # before making any changes to the database, or mysqld won't be able to write # to it later (this can be fixed with 'chown -R mysql.mysql /var/lib/mysql'). # To allow outside connections to the database comment out the next line. # If you don't need incoming network connections, then leave the line # uncommented to improve system security. #SKIP="--skip-networking" # Start mysqld: mysqld_start() { if [ -x /usr/bin/mysqld_safe ]; then # If there is an old PID file (no mysqld running), clean it up: if [ -r /var/run/mysql/mysql.pid ]; then if ! ps axc | grep mysqld 1> /dev/null 2> /dev/null ; then echo "Cleaning up old /var/run/mysql/mysql.pid." rm -f /var/run/mysql/mysql.pid fi fi /usr/bin/mysqld_safe --datadir=/var/lib/mysql --pid-file=/var/run/mysql/mysql.pid $SKIP & fi } # Stop mysqld: mysqld_stop() { # If there is no PID file, ignore this request... if [ -r /var/run/mysql/mysql.pid ]; then killall mysqld # Wait at least one minute for it to exit, as we don't know how big the DB is... for second in 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 \ 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 60 ; do if [ ! -r /var/run/mysql/mysql.pid ]; then break; fi sleep 1 done if [ "$second" = "60" ]; then echo "WARNING: Gave up waiting for mysqld to exit!" sleep 15 fi fi } # Restart mysqld: mysqld_restart() { mysqld_stop mysqld_start } case "$1" in 'start') mysqld_start ;; 'stop') mysqld_stop ;; 'restart') mysqld_restart ;; *) echo "usage $0 start|stop|restart" esac But there's also an unexpected init script on the machine, named /etc/init.d/mysql: #!/bin/sh # Copyright Abandoned 1996 TCX DataKonsult AB & Monty Program KB & Detron HB # This file is public domain and comes with NO WARRANTY of any kind # MySQL daemon start/stop script. # Usually this is put in /etc/init.d (at least on machines SYSV R4 based # systems) and linked to /etc/rc3.d/S99mysql and /etc/rc0.d/K01mysql. # When this is done the mysql server will be started when the machine is # started and shut down when the systems goes down. # Comments to support chkconfig on RedHat Linux # chkconfig: 2345 64 36 # description: A very fast and reliable SQL database engine. # Comments to support LSB init script conventions ### BEGIN INIT INFO # Provides: mysql # Required-Start: $local_fs $network $remote_fs # Should-Start: ypbind nscd ldap ntpd xntpd # Required-Stop: $local_fs $network $remote_fs # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: start and stop MySQL # Description: MySQL is a very fast and reliable SQL database engine. ### END INIT INFO # If you install MySQL on some other places than /usr, then you # have to do one of the following things for this script to work: # # - Run this script from within the MySQL installation directory # - Create a /etc/my.cnf file with the following information: # [mysqld] # basedir=<path-to-mysql-installation-directory> # - Add the above to any other configuration file (for example ~/.my.ini) # and copy my_print_defaults to /usr/bin # - Add the path to the mysql-installation-directory to the basedir variable # below. # # If you want to affect other MySQL variables, you should make your changes # in the /etc/my.cnf, ~/.my.cnf or other MySQL configuration files. # If you change base dir, you must also change datadir. These may get # overwritten by settings in the MySQL configuration files. #basedir= #datadir= # Default value, in seconds, afterwhich the script should timeout waiting # for server start. # Value here is overriden by value in my.cnf. # 0 means don't wait at all # Negative numbers mean to wait indefinitely service_startup_timeout=900 # The following variables are only set for letting mysql.server find things. # Set some defaults pid_file=/var/run/mysql/mysql.pid server_pid_file=/var/run/mysql/mysql.pid use_mysqld_safe=1 user=mysql if test -z "$basedir" then basedir=/usr bindir=/usr/bin if test -z "$datadir" then datadir=/var/lib/mysql fi sbindir=/usr/sbin libexecdir=/usr/libexec else bindir="$basedir/bin" if test -z "$datadir" then datadir="$basedir/data" fi sbindir="$basedir/sbin" libexecdir="$basedir/libexec" fi # datadir_set is used to determine if datadir was set (and so should be # *not* set inside of the --basedir= handler.) datadir_set= # # Use LSB init script functions for printing messages, if possible # lsb_functions="/lib/lsb/init-functions" if test -f $lsb_functions ; then . $lsb_functions else log_success_msg() { echo " SUCCESS! $@" } log_failure_msg() { echo " ERROR! $@" } fi PATH=/sbin:/usr/sbin:/bin:/usr/bin:$basedir/bin export PATH mode=$1 # start or stop shift other_args="$*" # uncommon, but needed when called from an RPM upgrade action # Expected: "--skip-networking --skip-grant-tables" # They are not checked here, intentionally, as it is the resposibility # of the "spec" file author to give correct arguments only. case `echo "testing\c"`,`echo -n testing` in *c*,-n*) echo_n= echo_c= ;; *c*,*) echo_n=-n echo_c= ;; *) echo_n= echo_c='\c' ;; esac parse_server_arguments() { for arg do case "$arg" in --basedir=*) basedir=`echo "$arg" | sed -e 's/^[^=]*=//'` bindir="$basedir/bin" if test -z "$datadir_set"; then datadir="$basedir/data" fi sbindir="$basedir/sbin" libexecdir="$basedir/libexec" ;; --datadir=*) datadir=`echo "$arg" | sed -e 's/^[^=]*=//'` datadir_set=1 ;; --user=*) user=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --pid-file=*) server_pid_file=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --service-startup-timeout=*) service_startup_timeout=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --use-mysqld_safe) use_mysqld_safe=1;; --use-manager) use_mysqld_safe=0;; esac done } parse_manager_arguments() { for arg do case "$arg" in --pid-file=*) pid_file=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; --user=*) user=`echo "$arg" | sed -e 's/^[^=]*=//'` ;; esac done } wait_for_pid () { verb="$1" manager_pid="$2" # process ID of the program operating on the pid-file i=0 avoid_race_condition="by checking again" while test $i -ne $service_startup_timeout ; do case "$verb" in 'created') # wait for a PID-file to pop into existence. test -s $pid_file && i='' && break ;; 'removed') # wait for this PID-file to disappear test ! -s $pid_file && i='' && break ;; *) echo "wait_for_pid () usage: wait_for_pid created|removed manager_pid" exit 1 ;; esac # if manager isn't running, then pid-file will never be updated if test -n "$manager_pid"; then if kill -0 "$manager_pid" 2>/dev/null; then : # the manager still runs else # The manager may have exited between the last pid-file check and now. if test -n "$avoid_race_condition"; then avoid_race_condition="" continue # Check again. fi # there's nothing that will affect the file. log_failure_msg "Manager of pid-file quit without updating file." return 1 # not waiting any more. fi fi echo $echo_n ".$echo_c" i=`expr $i + 1` sleep 1 done if test -z "$i" ; then log_success_msg return 0 else log_failure_msg return 1 fi } # Get arguments from the my.cnf file, # the only group, which is read from now on is [mysqld] if test -x ./bin/my_print_defaults then print_defaults="./bin/my_print_defaults" elif test -x $bindir/my_print_defaults then print_defaults="$bindir/my_print_defaults" elif test -x $bindir/mysql_print_defaults then print_defaults="$bindir/mysql_print_defaults" else # Try to find basedir in /etc/my.cnf conf=/etc/my.cnf print_defaults= if test -r $conf then subpat='^[^=]*basedir[^=]*=\(.*\)$' dirs=`sed -e "/$subpat/!d" -e 's//\1/' $conf` for d in $dirs do d=`echo $d | sed -e 's/[ ]//g'` if test -x "$d/bin/my_print_defaults" then print_defaults="$d/bin/my_print_defaults" break fi if test -x "$d/bin/mysql_print_defaults" then print_defaults="$d/bin/mysql_print_defaults" break fi done fi # Hope it's in the PATH ... but I doubt it test -z "$print_defaults" && print_defaults="my_print_defaults" fi # # Read defaults file from 'basedir'. If there is no defaults file there # check if it's in the old (depricated) place (datadir) and read it from there # extra_args="" if test -r "$basedir/my.cnf" then extra_args="-e $basedir/my.cnf" else if test -r "$datadir/my.cnf" then extra_args="-e $datadir/my.cnf" fi fi parse_server_arguments `$print_defaults $extra_args mysqld server mysql_server mysql.server` # Look for the pidfile parse_manager_arguments `$print_defaults $extra_args manager` # # Set pid file if not given # if test -z "$pid_file" then pid_file=$datadir/mysqlmanager-`/bin/hostname`.pid else case "$pid_file" in /* ) ;; * ) pid_file="$datadir/$pid_file" ;; esac fi if test -z "$server_pid_file" then server_pid_file=$datadir/`/bin/hostname`.pid else case "$server_pid_file" in /* ) ;; * ) server_pid_file="$datadir/$server_pid_file" ;; esac fi case "$mode" in 'start') # Start daemon # Safeguard (relative paths, core dumps..) cd $basedir manager=$bindir/mysqlmanager if test -x $libexecdir/mysqlmanager then manager=$libexecdir/mysqlmanager elif test -x $sbindir/mysqlmanager then manager=$sbindir/mysqlmanager fi echo $echo_n "Starting MySQL" if test -x $manager -a "$use_mysqld_safe" = "0" then if test -n "$other_args" then log_failure_msg "MySQL manager does not support options '$other_args'" exit 1 fi # Give extra arguments to mysqld with the my.cnf file. This script may # be overwritten at next upgrade. $manager --user=$user --pid-file=$pid_file >/dev/null 2>&1 & wait_for_pid created $!; return_value=$? # Make lock for RedHat / SuSE if test -w /var/lock/subsys then touch /var/lock/subsys/mysqlmanager fi exit $return_value elif test -x $bindir/mysqld_safe then # Give extra arguments to mysqld with the my.cnf file. This script # may be overwritten at next upgrade. pid_file=$server_pid_file $bindir/mysqld_safe --datadir=$datadir --pid-file=$server_pid_file $other_args >/dev/null 2>&1 & wait_for_pid created $!; return_value=$? # Make lock for RedHat / SuSE if test -w /var/lock/subsys then touch /var/lock/subsys/mysql fi exit $return_value else log_failure_msg "Couldn't find MySQL manager ($manager) or server ($bindir/mysqld_safe)" fi ;; 'stop') # Stop daemon. We use a signal here to avoid having to know the # root password. # The RedHat / SuSE lock directory to remove lock_dir=/var/lock/subsys/mysqlmanager # If the manager pid_file doesn't exist, try the server's if test ! -s "$pid_file" then pid_file=$server_pid_file lock_dir=/var/lock/subsys/mysql fi if test -s "$pid_file" then mysqlmanager_pid=`cat $pid_file` echo $echo_n "Shutting down MySQL" kill $mysqlmanager_pid # mysqlmanager should remove the pid_file when it exits, so wait for it. wait_for_pid removed "$mysqlmanager_pid"; return_value=$? # delete lock for RedHat / SuSE if test -f $lock_dir then rm -f $lock_dir fi exit $return_value else log_failure_msg "MySQL manager or server PID file could not be found!" fi ;; 'restart') # Stop the service and regardless of whether it was # running or not, start it again. if $0 stop $other_args; then $0 start $other_args else log_failure_msg "Failed to stop running server, so refusing to try to start." exit 1 fi ;; 'reload'|'force-reload') if test -s "$server_pid_file" ; then read mysqld_pid < $server_pid_file kill -HUP $mysqld_pid && log_success_msg "Reloading service MySQL" touch $server_pid_file else log_failure_msg "MySQL PID file could not be found!" exit 1 fi ;; 'status') # First, check to see if pid file exists if test -s "$server_pid_file" ; then read mysqld_pid < $server_pid_file if kill -0 $mysqld_pid 2>/dev/null ; then log_success_msg "MySQL running ($mysqld_pid)" exit 0 else log_failure_msg "MySQL is not running, but PID file exists" exit 1 fi else # Try to find appropriate mysqld process mysqld_pid=`pidof $sbindir/mysqld` if test -z $mysqld_pid ; then if test "$use_mysqld_safe" = "0" ; then lockfile=/var/lock/subsys/mysqlmanager else lockfile=/var/lock/subsys/mysql fi if test -f $lockfile ; then log_failure_msg "MySQL is not running, but lock exists" exit 2 fi log_failure_msg "MySQL is not running" exit 3 else log_failure_msg "MySQL is running but PID file could not be found" exit 4 fi fi ;; *) # usage echo "Usage: $0 {start|stop|restart|reload|force-reload|status} [ MySQL server options ]" exit 1 ;; esac exit 0 An unimportant aside: The previous users of the machine kept a messy home directory. Their home directory was /root. I've pasted a copy at http://www.pastebin.ca/2167496. My question: Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there? P.S. This question is far from perfect. Please feel free to edit it.

  Read the article

• What packages are safe to uninstall to reduce installation size?

  - by mathematician1975

  This question is similar to a previous question I asked How can I turn my desktop Ubuntu 8.04 into a command line only install?. I was wondering if anyone can recommend any other bulky packages from the standard 8.04 installation that can reduce the size on disk of my installation. All I really require is socket functionality, g++ and gcc, some kind of text editor and SSH client and server. Things that I don't require are things like media players, audio packages, and the more "superficial" kind of desktop niceties. Is there anything particularly large in a standard install that is safe for me to remove without compromising my requirements above? I am a bit apprehensive about trying to uninstall items and I am not totally confident about removal of particular things having a negative effect on the functionality of any other things I might need (an example is would it be safe for me to remove everything to do with Perl, or does the system/kernel/other processes require this) ??? Basically I would like to be left with the kind of items that would have been installed in the CLI version of 8.04 (had the alternative iso image not been faulty). Any help/suggestions would be gratefully received.

  Read the article

• Cannot connect to MySQL with JDBC - Connection Timeout - Ubuntu 9.04

  - by gav

  I am running Ubuntu and am ultimately trying to connect Tomcat to my MySQL database using JDBC. It has worked previously but after a reboot the instance now fails to connect. Both Tomcat 6 and MySQL 5.0.75 are on the same machine Connection string: jdbc:mysql:///localhost:3306 I can connect to MySQL on the command line using the mysql command The my.cnf file is pretty standard (Available on request) has bind address: 127.0.0.1 I cannot Telnet to the MySQL port despite netstat saying MySQL is listening I have one IpTables rule to forward 80 - 8080 and no firewall I'm aware of. I'm pretty new to this and I'm not sure what else to test. I don't know whether I should be looking in etc/interfaces and if I did what to look for. It's weird because it used to work but after a reboot it's down so I must have changed something.... :). I realise a timeout indicates the server is not responding and I assume it's because the request isn't actually getting through. I installed MySQL via apt-get and Tomcat manually. MySqld processes root@88:/var/log/mysql# ps -ef | grep mysqld root 21753 1 0 May27 ? 00:00:00 /bin/sh /usr/bin/mysqld_safe mysql 21792 21753 0 May27 ? 00:00:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.pid --skip-external-locking --port=3306 --socket=/var/run/mysqld/mysqld.sock root 21793 21753 0 May27 ? 00:00:00 logger -p daemon.err -t mysqld_safe -i -t mysqld root 21888 13676 0 11:23 pts/1 00:00:00 grep mysqld Netstat root@88:/var/log/mysql# netstat -lnp | grep mysql tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 21792/mysqld unix 2 [ ACC ] STREAM LISTENING 1926205077 21792/mysqld /var/run/mysqld/mysqld.sock Toy Connection Class root@88:~# cat TestConnect/TestConnection.java import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; public class TestConnection { public static void main(String args[]) throws Exception { Connection con = null; try { Class.forName("com.mysql.jdbc.Driver").newInstance(); System.out.println("Got driver"); con = DriverManager.getConnection( "jdbc:mysql:///localhost:3306", "uname", "pass"); System.out.println("Got connection"); if(!con.isClosed()) System.out.println("Successfully connected to " + "MySQL server using TCP/IP..."); } finally { if(con != null) con.close(); } } } Toy Connection Class Output Note: This is the same error I get from Tomcat. root@88:~/TestConnect# java -cp mysql-connector-java-5.1.12-bin.jar:. TestConnection Got driver Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was 1 milliseconds ago. The driver has not received any packets from the server. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at com.mysql.jdbc.Util.handleNewInstance(Util.java:409) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122) at TestConnection.main(TestConnection.java:14) Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at com.mysql.jdbc.Util.handleNewInstance(Util.java:409) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:344) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2181) ... 12 more Caused by: java.net.ConnectException: Connection timed out at java.net.PlainSocketImpl.socketConnect(Native Method) ... 13 more Telnet Output root@88:~/TestConnect# telnet localhost 3306 Trying 127.0.0.1... telnet: Unable to connect to remote host: Connection timed out

  Read the article

• General logging won't work in MySQL

  - by leonstr

  I saw on SF that there's an option in MySQL to log all queries. So, in my version (mysql-server-5.0.45-7.el5 on CentOS 5.2) this appears to be a case of enabling the 'log' option, so I edited /etc/my.cnf to add this: [mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock user=mysql old_passwords= log=/var/log/mysql-general.log [mysqld_safe] log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid I then created the file and set permissions: # touch /var/log/mysql-general.log # chown mysql. /var/log/mysql-general.log # ls -l /var/log/mysql-general.log -rw-r--r-- 1 mysql mysql 0 Jan 18 15:22 /var/log/mysql-general.log But when I start mysqld I get: 120118 15:24:18 mysqld started ^G/usr/libexec/mysqld: File '/var/log/mysql-general.log' not found (Errcode: 13) 120118 15:24:18 [ERROR] Could not use /var/log/mysql-general.log for logging (error 13). Turning logging off for the whole duration of the MySQL server process. To turn it on again: fix the cause, shutdown the MySQL server and restart it. 120118 15:24:18 InnoDB: Started; log sequence number 0 182917764 120118 15:24:18 [Note] /usr/libexec/mysqld: ready for connections. Can anyone suggest why this isn't working?

  Read the article

• MySQL not releasing temp file descriptors

  - by Wakaru44

  Since a few days ago, we’ve been experiencing some serious problems with our MySQL installation: MySQL keeps opening temporal files (normal behaviour) but these files are never released. The consequence is that, eventually, the disk space is exhausted and we have to restart the service and clean up /tmp manually. Using lsof, we see something like this: mysqld 16866 mysql 5u REG 8,3 0 692 /tmp/ibyWJylQ (deleted) mysqld 16866 mysql 6u REG 8,3 0 707 /tmp/ibf5adsT (deleted) mysqld 16866 mysql 7u REG 8,3 0 728 /tmp/ibGjPRyW (deleted) mysqld 16866 mysql 8u REG 8,3 0 5678 /tmp/ibMQDLMZ (deleted) mysqld 16866 mysql 13u REG 8,3 0 5679 /tmp/ibQAnM42 (deleted) Maybe it's not related, but when we shutdown the server, the files are finally freed, and we can see the following warnings in the MySQL log: 121029 7:44:27 [Warning] /usr/local/mysql/bin/mysqld: Forcing close of thread 1333 user: 'xxx' 121029 7:44:27 [Warning] /usr/local/mysql/bin/mysqld: Forcing close of thread 1156 user: 'yyy' 121029 7:44:27 [Warning] /usr/local/mysql/bin/mysqld: Forcing close of thread 1151 user: 'zzz' where 'xxx', 'yyy' and 'zzz' are distinct mysql users (and the only 3 users with active connections to the database). We have a few theories: There is a problem in the OS, that keeps file handlers open. Could it be possible that the OS "delete" operation blocks the threads until shutdown? This may explain the warning at shutdown and the fact that files are finally deleted when the process dies. Until now, data sets were so small that temp files were relatively small and there was enough time to release the file handles without exhausting disk space. We are using Mysql 5.5 on a RHEL 6.2 with the default kernel.

  Read the article

• What am I doing wrong in my config for MySql?

  - by Knight Hawk3

  When I load my my.conf with the config at the bottom Mysql fails to start and prints no errors. I am running Arch Linux (Updated) with the latest MySQL (5.5) and the latest nginx (Well latest in the repository, Not sure how to check. Only installed it today) I will give you any info you ask for. Thanks for helping! # The following options will be passed to all MySQL clients [client] #password = your_password port = 3306 socket = /var/run/mysqld/mysqld.sock # Here follows entries for some specific programs # The MySQL server [mysqld] port = 3306 socket = /var/run/mysqld/mysqld.sock skip-locking key_buffer = 16K max_allowed_packet = 1M table_cache = 4 sort_buffer_size = 64K read_buffer_size = 256K read_rnd_buffer_size = 256K net_buffer_length = 2K thread_stack = 64K # Don’t listen on a TCP/IP port at all. This can be a security enhancement, # if all processes that need to connect to mysqld run on the same host. # All interaction with mysqld must be made via Unix sockets or named pipes. # Note that using this option without enabling named pipes on Windows # (using the “enable-named-pipe” option) will render mysqld useless! # #skip-networking server-id = 1 # Uncomment the following if you want to log updates #log-bin=mysql-bin # Uncomment the following if you are NOT using BDB tables skip-bdb # Uncomment the following if you are using InnoDB tables #innodb_data_home_dir = /var/lib/mysql/ #innodb_data_file_path = ibdata1:10M:autoextend #innodb_log_group_home_dir = /var/lib/mysql/ #innodb_log_arch_dir = /var/lib/mysql/ # You can set .._buffer_pool_size up to 50 – 80 % # of RAM but beware of setting memory usage too high #innodb_buffer_pool_size = 16M #innodb_additional_mem_pool_size = 2M # Set .._log_file_size to 25 % of buffer pool size #innodb_log_file_size = 5M #innodb_log_buffer_size = 8M #innodb_flush_log_at_trx_commit = 1 #innodb_lock_wait_timeout = 50 skip-innodb [mysqldump] quick max_allowed_packet = 16M [mysql] no-auto-rehash # Remove the next comment character if you are not familiar with SQL #safe-updates [isamchk] key_buffer = 1M sort_buffer_size = 1M [myisamchk] key_buffer = 1M sort_buffer_size = 1M [mysqlhotcopy] interactive-timeout So what is my silly error?

  Read the article

• Fresh 12.04 Install - mySQL not starting

  - by Lee Armstrong

  I have a freshly installed Ubuntu 12.04 x64 server and I installed Percona server from their official repositories. Trouble is it will not start! mysql-error.log shows nothing obvious. 121129 12:16:54 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql/ 121129 12:16:54 [Note] Plugin 'FEDERATED' is disabled. 121129 12:16:54 InnoDB: The InnoDB memory heap is disabled 121129 12:16:54 InnoDB: Mutexes and rw_locks use GCC atomic builtins 121129 12:16:54 InnoDB: Compressed tables use zlib 1.2.3 121129 12:16:54 InnoDB: Using Linux native AIO 121129 12:16:54 InnoDB: Initializing buffer pool, size = 12.0G 121129 12:16:54 InnoDB: Completed initialization of buffer pool 121129 12:16:54 InnoDB: highest supported file format is Barracuda. 121129 12:16:55 InnoDB: Waiting for the background threads to start 121129 12:16:56 Percona XtraDB (http://www.percona.com) 1.1.8-rel29.1 started; log sequence number 1598476 121129 12:16:56 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306 121129 12:16:56 [Note] - '0.0.0.0' resolves to '0.0.0.0'; 121129 12:16:56 [Note] Server socket created on IP: '0.0.0.0'. 121129 12:16:56 [Note] Event Scheduler: Loaded 0 events 121129 12:16:56 [Note] /usr/sbin/mysqld: ready for connections. Version: '5.5.28-29.1-log' socket: '/var/run/mysqld/mysql.sock' port: 3306 Percona Server (GPL), Release 29.1 121129 12:16:56 [Note] Event Scheduler: scheduler thread started with id 1 And the syslog shows... Nov 29 12:17:07 V-PF-SQL1 /etc/init.d/mysql[2206]: 0 processes alive and '/usr/bin/mysqladmin --defaults-file=/etc/mysql/debian.cnf ping' resulted in Nov 29 12:17:07 V-PF-SQL1 /etc/init.d/mysql[2206]: #007/usr/bin/mysqladmin: connect to server at 'localhost' failed Nov 29 12:17:07 V-PF-SQL1 /etc/init.d/mysql[2206]: error: 'Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)' Nov 29 12:17:07 V-PF-SQL1 /etc/init.d/mysql[2206]: Check that mysqld is running and that the socket: '/var/run/mysqld/mysqld.sock' exists! Nov 29 12:17:07 V-PF-SQL1 /etc/init.d/mysql[2206]: The socket file is being created and I can access the server NOT using the socket using mysql -h 127.0.0.1 -P 3306 -u root --pPASSWORD

  Read the article

• How Do I enable Safe Asynchronous Write With NFS?

  - by Joe Swanson

  The NFSv3 documentation talks alot about the concept of "safe asynchronous writes" (last bullet of A1): http://nfs.sourceforge.net/#section_a This is NOT referring to the sync/async option in the server exports file (as the async option in the exports file is NOT safe). As I understand it, safe asynchronous writes is a hybrid between the sync/async exports option. It allows for a server to reply back without flushing to stable storage immediately, but the client will not remove the write request from cache until it has received confirmation that it has been committed to stable storage (and also detects if the server looses power/reboots). I believe that this option is set on the client side, but I have not come across any documentation that shows how to do this. Any ideas?

  Read the article

• What is safe to exclude for a full system backup?

  - by seb

  Hi, I'm looking for a list which paths/files are safe to exclude for a full system/home backup. Considering that I have a list of installed packages. /home/*/.thumbnails /home/*/.cache /home/*/.mozilla/firefox/*.default/Cache /home/*/.mozilla/firefox/*.default/OfflineCache /home/*/.local/share/Trash /home/*/.gvfs/ /tmp/ /var/tmp/ not real folders but can cause severe problems when 'restoring' /dev /proc /sys What about... /var/ in general? /var/backups/ - can get quite large /var/log/ - does not require much space and can help for later comparison /lost+found/

  Read the article

• Safe to update separate regions of a BufferedImage in separate threads?

  - by finnw

  I have a collection of BufferedImage instances, one main image and some subimages created by calling getSubImage on the main image. The subimages do not overlap. I am also making modifications to the subimage and I want to split this into multiple threads, one per subimage. From my understanding of how BufferedImage, Raster and DataBuffer work, this should be safe because: Each instance of BufferedImage (and its respective WritableRaster) is accessed from only one thread. The shared ColorModel is immutable The DataBuffer has no fields that can be modified (the only thing that can change is elements of the backing array.) Modifying disjoint segments of an array in separate threads is safe. However I cannot find anything in the documentation that says that it is definitely safe to do this. Can I assume it is safe? I know that it is possible to work on copies of the child Rasters but I would prefer to avoid this because of memory constraints. Otherwise, is it possible to make the operation thread-safe without copying regions of the parent image?

  Read the article

< Previous Page | 15 16 17 18 19 20 21 22 23 24 25 26  | Next Page >