Search Results

Search found 13829 results on 554 pages for 'temporary objects'.

Page 92/554 | < Previous Page | 88 89 90 91 92 93 94 95 96 97 98 99  | Next Page >

• what is the purpose of numeric/boolean/string objects as opposed to primitive values?

  - by zespri

  In javascript you can call a function as a function or as a constructor. For example you can do : myObject = new Number(13); myPrimitiveValue = Number(13); or simply myPrimitiveValue = 13; I understand the difference between the results. Can you explain me under which reasonable circumstances creating a number, a boolean or a string as an object is desirable? For example, ability to set new properties (this is something you can do on objects but can't really do on primitive values) is almost always a bad idea for objects containing number/boolean/string. Why would I want a numeric/boolean/string object?

  Read the article

• How to efficiently use Enum objects as keys in the Map data structure?

  - by yamsha

  Is there a more efficient and specialized implementation of a Map collection where Enum objects can serve as keys?

  Read the article

• c++ link temporary allocations in fuction to custom allocator?

  - by user300713

  Hi, I am currently working on some simple custom allocators in c++ which generally works allready. I also overloaded the new/delete operators to allocate memory from my own allocator. Anyways I came across some scenarios where I don't really know where the memory comes from like this: void myFunc(){ myObj testObj(); ....do something with it } In this case testObj would only be valid inside the function, but where would its memory come from? Is there anyway I could link it to my allocator? Would I have to create to object using new and delete or is there another way? Thanks

  Read the article

• Should my DAOs (Database Entities) Directly match my UI Objects?

  - by scarpacci

  I am trying to figure out best practice for N-Tier application design. When designing the objects my UI needs and those that will be persisted in the DB some of my colleagues are suggesting that the objects be one in the same. This doesn't not feel right to me and I am ultimately looking for some best practice documentation to help me in this decision. I honestly do not understand why I would want to design this way given that other applications may want to interact with my Data Access Layer....or it is just ignorance or lack of understanding on my part. Any documentation, information you could provide would be greatly appreciated. Just want to better understand these concepts and I am having a hard time finding some good information on the best practice for implementing these patterns (Or it is right in front of me on what I found and I didn't understand what was being outlined). Thanks, S

  Read the article

• Unable to generate a temporary class (result=1). error CS0030: Cannot convert type 'Type[]' to 'Type'?

  - by grady

  I get this error after I created a class from my xsd file using the xsd.exe tool. So I searched the net and found a solution. Here is the link: http://satov.blogspot.com/2006/12/xsdexe-generated-classes-causing.html Problem is that this makes the code run, but somehow the deserialized data seems corrupt. I did what the site suggests and in the end the 2nd array dimension is always empty (see the comments of the site, somebody also had this problem). Question is, how do I solve this issue now? Is there another tool to create the xsd file? I tried Xsd2Code, without success. Thanks :-)

  Read the article

• Is this a safe way to reference objects in JavaScript?

  - by John

  If I were to define two objects myDataStore and myDrawer something like this: var myDataStore = function(myObjectRef) { this.myInternalObject = myObjectRef; }; var myDrawer = function(myObjRef) { this.myInternalObject = myObjectRef; }; And if I were to create an object like so: (function(){ var myObject = window.myObject = function(){ this.dataStore = new myDataStore(this); this.drawer = new myDrawer(this); } })(); Then myObject.dataStore.myInternalObject, and myObject.drawer.myInternalObject, would simply be pointers back to the original 'myObject' - not taking up any additional memory in the browser. Yes? I am interested in implementing techniques like this - as it makes it easy for objects to communicate with each other.

  Read the article

• Is it poor practice to identify objects via an enumeration property, instead of using GetType()?

  - by James

  I have a collection of objects that all implement one (custom) interface: IAuditEvent. Each object can be stored in a database and a unique numeric id is used for each object type. The method that stores the objects loops around a List<IAuditEvent>, so it needs to know the specific type of each object in order to store the correct numeric id. Is it poor practice to have an enumeration property on IAuditEvent so that each object can identify itself with a unique enumeration value? I can see that the simplest solution would be to write a method that translates a Type into an integer, but what if I need an enumeration of audit events for another purpose? Would it still be wrong to have my enumeration property on IAuditEvent?

  Read the article

• Allow users to pull temporary data then delete table data (headers remain)?

  - by JM4

  I don't know the best way to title this question but am trying to accomplish the following goal: When a client logs into their profile, they are presented with a link to download data from an existing database in CSV format. The process works, however, I would like for this data to be 'fresh' each time they click the link so my plan was - once a user has clicked the link and downloaded the CSV file, the database table would 'erase' all of its data and start fresh (be empty) until the next set of data populated it. My EXISTING CSV creation code: <?php $host = 'localhost'; $user = 'username'; $pass = 'password'; $db = 'database'; $table = 'tablename'; $file = 'export'; $link = mysql_connect($host, $user, $pass) or die("Can not connect." . mysql_error()); mysql_select_db($db) or die("Can not connect."); $result = mysql_query("SHOW COLUMNS FROM ".$table.""); $i = 0; if (mysql_num_rows($result) > 0) { while ($row = mysql_fetch_assoc($result)) { $csv_output .= $row['Field'].", "; $i++; } } $csv_output .= "\n"; $values = mysql_query("SELECT * FROM ".$table.""); while ($rowr = mysql_fetch_row($values)) { for ($j=0;$j<$i;$j++) { $csv_output .= '"'.$rowr[$j].'",'; } $csv_output .= "\n"; } $filename = $file."_".date("Y-m-d",time()); header("Content-type: application/vnd.ms-excel"); header("Content-disposition: csv" . date("Y-m-d") . ".csv"); header( "Content-disposition: filename=".$filename.".csv"); print $csv_output; exit; ?> any ideas?

  Read the article

• Fusion Concepts: Fusion Database Schemas

  - by Vik Kumar

  You often read about FUSION and FUSION_RUNTIME users while dealing with Fusion Applications. There is one more called FUSION_DYNAMIC. Here are some details on the difference between these three and the purpose of each type of schema. FUSION: It can be considered as an Administrator of the Fusion Applications with all the corresponding rights and powers such as owning tables and objects, providing grants to FUSION_RUNTIME.  It is used for patching and has grants to many internal DBMS functions. FUSION_RUNTIME: Used to run the Applications.  Contains no DB objects. FUSION_DYNAMIC: This schema owns the objects that are created dynamically through ADM_DDL. ADM_DDL is a package that acts as a wrapper around the DDL statement. ADM_DDL support operations like truncate table, create index etc. As the above statements indicate that FUSION owns the tables and objects including FND tables so using FUSION to run applications is insecure. It would be possible to modify security policies and other key information in the base tables (like FND) to break the Fusion Applications security via SQL injection etc. Other possibilities would be to write a logon DB trigger and steal credentials etc. Thus, to make Fusion Applications secure FUSION_RUNTIME is granted privileges to execute DMLs only on APPS tables. Another benefit of having separate users is achieving Separation of Duties (SODs) at schema level which is required by auditors. Below are the roles and privileges assigned to FUSION, FUSION_RUNTIME and FUSION_DYNAMIC schema: FUSION It has the following privileges: Create SESSION Do all types of DDL owned by FUSION. Additionally, some specific priveleges on other schemas is also granted to FUSION. EXECUTE ON various EDN_PUBLISH_EVENT It has the following roles: CTXAPP for managing Oracle Text Objects AQ_SER_ROLE and AQ_ADMINISTRATOR_ROLE for managing Advanced Queues (AQ) FUSION_RUNTIME It has the following privileges: CREATE SESSION CHANGE NOTIFICATION EXECUTE ON various EDN_PUBLISH_EVENT It has the following roles: FUSION_APPS_READ_WRITE for performing DML (Select, Insert, Delete) on Fusion Apps tables FUSION_APPS_EXECUTE for performing execute on objects such as procedures, functions, packages etc. AQ_SER_ROLE and AQ_ADMINISTRATOR_ROLE for managing Advanced Queues (AQ) FUSION_DYNAMIC It has following privileges: CREATE SESSION, PROCEDURE, TABLE, SEQUENCE, SYNONYM, VIEW UNLIMITED TABLESPACE ANALYZE ANY CREATE MINING MODEL EXECUTE on specific procedure, function or package and SELECT on specific tables. This depends on the objects identified by product teams that ADM_DDL needs to have access  in order to perform dynamic DDL statements. There is one more role FUSION_APPS_READ_ONLY which is not attached to any user and has only SELECT privilege on all the Fusion objects. FUSION_RUNTIME does not have any synonyms defined to access objects owned by FUSION schema. A logon trigger is defined in FUSION_RUNTIME which sets the current schema to FUSION and eliminates the need of any synonyms.   What it means for developers? Fusion Application developers should be using FUSION_RUNTIME for testing and running Fusion Applications UI, BC and to connect to any SQL front end like SQL *PLUS, SQL Loader etc. For testing ADFbc using AM tester while using FUSION_RUNTIME you may hit the following error: oracle.jbo.JboException: JBO-29000: Unexpected exception caught: java.sql.SQLException, msg=invalid name pattern: FUSION.FND_TABLE_OF_VARCHAR2_255 The fix is to add the below JVM parameter in the Run/Debug client property in the Model project properties -Doracle.jdbc.createDescriptorUseCurrentSchemaForSchemaName=true More details are discussed in this forum thread for it.

  Read the article

• Patterns for a tree of persistent data with multiple storage options?

  - by Robin Winslow

  I have a real-world problem which I'll try to abstract into an illustrative example. So imagine I have data objects in a tree, where parent objects can access children, and children can access parents: // Interfaces interface IParent<TChild> { List<TChild> Children; } interface IChild<TParent> { TParent Parent; } // Classes class Top : IParent<Middle> {} class Middle : IParent<Bottom>, IChild<Top> {} class Bottom : IChild<Middle> {} // Usage var top = new Top(); var middles = top.Children; // List<Middle> foreach (var middle in middles) { var bottoms = middle.Children; // List<Bottom> foreach (var bottom in bottoms) { var middle = bottom.Parent; // Access the parent var top = middle.Parent; // Access the grandparent } } All three data objects have properties that are persisted in two data stores (e.g. a database and a web service), and they need to reflect and synchronise with the stores. Some objects only request from the web service, some only write to it. Data Mapper My favourite pattern for data access is Data Mapper, because it completely separates the data objects themselves from the communication with the data store: class TopMapper { public Top FetchById(int id) { var top = new Top(DataStore.TopDataById(id)); top.Children = MiddleMapper.FetchForTop(Top); return Top; } } class MiddleMapper { public Middle FetchById(int id) { var middle = new Middle(DataStore.MiddleDataById(id)); middle.Parent = TopMapper.FetchForMiddle(middle); middle.Children = BottomMapper.FetchForMiddle(bottom); return middle; } } This way I can have one mapper per data store, and build the object from the mapper I want, and then save it back using the mapper I want. There is a circular reference here, but I guess that's not a problem because most languages can just store memory references to the objects, so there won't actually be infinite data. The problem with this is that every time I want to construct a new Top, Middle or Bottom, it needs to build the entire object tree within that object's Parent or Children property, with all the data store requests and memory usage that that entails. And in real life my tree is much bigger than the one represented here, so that's a problem. Requests in the object In this the objects request their Parents and Children themselves: class Middle { private List<Bottom> _children = null; // cache public List<Bottom> Children { get { _children = _children ?? BottomMapper.FetchForMiddle(this); return _children; } set { BottomMapper.UpdateForMiddle(this, value); _children = value; } } } I think this is an example of the repository pattern. Is that correct? This solution seems neat - the data only gets requested from the data store when you need it, and thereafter it's stored in the object if you want to request it again, avoiding a further request. However, I have two different data sources. There's a database, but there's also a web service, and I need to be able to create an object from the web service and save it back to the database and then request it again from the database and update the web service. This also makes me uneasy because the data objects themselves are no longer ignorant of the data source. We've introduced a new dependency, not to mention a circular dependency, making it harder to test. And the objects now mask their communication with the database. Other solutions Are there any other solutions which could take care of the multiple stores problem but also mean that I don't need to build / request all the data every time?

  Read the article

• Unable to receive any emails using postfix, dovecot, mysql, and virtual domain/mailboxes

  - by stkdev248

  I have been working on configuring my mail server for the last couple of weeks using postfix, dovecot, and mysql. I have one virtual domain and a few virtual mailboxes. Using squirrelmail I have been able to log into my accounts and send emails out (e.g. I can send to googlemail just fine), however I am not able to receive any emails--not from the outside world nor from within my own network. I am able to telnet in using localhost, my private ip, and my public ip on port 25 without any problems (I've tried it from the server itself and from another computer on my network). This is what I get in my logs when I send an email from my googlemail account to my mail server: mail.log Apr 14 07:36:06 server1 postfix/qmgr[1721]: BE01B520538: from=, size=733, nrcpt=1 (queue active) Apr 14 07:36:06 server1 postfix/pipe[3371]: 78BC0520510: to=, relay=dovecot, delay=45421, delays=45421/0/0/0.13, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied) Apr 14 07:36:06 server1 postfix/pipe[3391]: 8261B520534: to=, relay=dovecot, delay=38036, delays=38036/0.06/0/0.12, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:06 server1 postfix/pipe[3378]: 63927520532: to=, relay=dovecot, delay=38105, delays=38105/0.02/0/0.17, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:06 server1 postfix/pipe[3375]: 07F65520522: to=, relay=dovecot, delay=39467, delays=39467/0.01/0/0.17, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:06 server1 postfix/pipe[3381]: EEDE9520527: to=, relay=dovecot, delay=38361, delays=38360/0.04/0/0.15, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:06 server1 postfix/pipe[3379]: 67DFF520517: to=, relay=dovecot, delay=40475, delays=40475/0.03/0/0.16, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:06 server1 postfix/pipe[3387]: 3C7A052052E: to=, relay=dovecot, delay=38259, delays=38259/0.05/0/0.13, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:06 server1 postfix/pipe[3394]: BE01B520538: to=, relay=dovecot, delay=37682, delays=37682/0.07/0/0.11, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:36:07 server1 postfix/pipe[3384]: 3C7A052052E: to=, relay=dovecot, delay=38261, delays=38259/0.04/0/1.3, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:39:23 server1 postfix/anvil[3368]: statistics: max connection rate 1/60s for (smtp:209.85.213.169) at Apr 14 07:35:32 Apr 14 07:39:23 server1 postfix/anvil[3368]: statistics: max connection count 1 for (smtp:209.85.213.169) at Apr 14 07:35:32 Apr 14 07:39:23 server1 postfix/anvil[3368]: statistics: max cache size 1 at Apr 14 07:35:32 Apr 14 07:41:06 server1 postfix/qmgr[1721]: ED6005203B7: from=, size=1463, nrcpt=1 (queue active) Apr 14 07:41:06 server1 postfix/pipe[4594]: ED6005203B7: to=, relay=dovecot, delay=334, delays=334/0.01/0/0.13, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) Apr 14 07:51:06 server1 postfix/qmgr[1721]: ED6005203B7: from=, size=1463, nrcpt=1 (queue active) Apr 14 07:51:06 server1 postfix/pipe[4604]: ED6005203B7: to=, relay=dovecot, delay=933, delays=933/0.02/0/0.12, dsn=4.3.0, status=deferred (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ) mail-dovecot-log (the log I set for debugging): Apr 14 07:28:26 auth: Info: mysql(127.0.0.1): Connected to database postfixadmin Apr 14 07:28:26 auth: Debug: sql([email protected],127.0.0.1): query: SELECT password FROM mailbox WHERE username = '[email protected]' Apr 14 07:28:26 auth: Debug: client out: OK 1 [email protected] Apr 14 07:28:26 auth: Debug: master in: REQUEST 1809973249 3356 1 7cfb822db820fc5da67d0776b107cb3f Apr 14 07:28:26 auth: Debug: sql([email protected],127.0.0.1): SELECT '/home/vmail/mydomain.com/some.user1' as home, 5000 AS uid, 5000 AS gid FROM mailbox WHERE username = '[email protected]' Apr 14 07:28:26 auth: Debug: master out: USER 1809973249 [email protected] home=/home/vmail/mydomain.com/some.user1 uid=5000 gid=5000 Apr 14 07:28:26 imap-login: Info: Login: user=, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, mpid=3360, secured Apr 14 07:28:26 imap([email protected]): Debug: Effective uid=5000, gid=5000, home=/home/vmail/mydomain.com/some.user1 Apr 14 07:28:26 imap([email protected]): Debug: maildir++: root=/home/vmail/mydomain.com/some.user1/Maildir, index=/home/vmail/mydomain.com/some.user1/Maildir/indexes, control=, inbox=/home/vmail/mydomain.com/some.user1/Maildir Apr 14 07:48:31 imap([email protected]): Info: Disconnected: Logged out bytes=85/681 From the output above I'm pretty sure that my problems all stem from (temporary failure. Command output: Can't open log file /var/log/mail-dovecot.log: Permission denied ), but I have no idea why I'm getting that error. I've have the permissions to that log set just like the other mail logs: root@server1:~# ls -l /var/log/mail* -rw-r----- 1 syslog adm 196653 2012-04-14 07:58 /var/log/mail-dovecot.log -rw-r----- 1 syslog adm 62778 2012-04-13 21:04 /var/log/mail.err -rw-r----- 1 syslog adm 497767 2012-04-14 08:01 /var/log/mail.log Does anyone have any idea what I may be doing wrong? Here are my main.cf and master.cf files: main.cf: # See /usr/share/postfix/main.cf.dist for a commented, more complete version # Debian specific: Specifying a file name will cause the first # line of that file to be used as the name. The Debian default # is /etc/mailname. #myorigin = /etc/mailname smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) biff = no # appending .domain is the MUA's job. append_dot_mydomain = no # Uncomment the next line to generate "delayed mail" warnings #delay_warning_time = 4h readme_directory = no # TLS parameters smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key smtpd_use_tls=yes smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache # See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for # information on enabling SSL in the smtp client. myhostname = server1.mydomain.com alias_maps = hash:/etc/aliases alias_database = hash:/etc/aliases myorigin = /etc/mailname mydestination = relayhost = mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 mailbox_command = procmail -a "$EXTENSION" mailbox_size_limit = 0 recipient_delimiter = + inet_interfaces = all # Virtual Configs virtual_uid_maps = static:5000 virtual_gid_maps = static:5000 virtual_mailbox_base = /home/vmail virtual_mailbox_domains = mysql:/etc/postfix/mysql_virtual_mailbox_domains.cf virtual_mailbox_maps = mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf virtual_alias_maps = mysql:/etc/postfix/mysql_virtual_alias_maps.cf relay_domains = mysql:/etc/postfix/mysql_relay_domains.cf smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_non_fqdn_hostname, reject_non_fqdn_sender, reject_non_fqdn_recipient, reject_unauth_destination, reject_unauth_pipelining, reject_invalid_hostname smtpd_sasl_auth_enable = yes smtpd_sasl_security_options = noanonymous virtual_transport=dovecot dovecot_destination_recipient_limit = 1 master.cf: # # Postfix master process configuration file. For details on the format # of the file, see the master(5) manual page (command: "man 5 master"). # # Do not forget to execute "postfix reload" after editing this file. # # ========================================================================== # service type private unpriv chroot wakeup maxproc command + args # (yes) (yes) (yes) (never) (100) # ========================================================================== smtp inet n - - - - smtpd #smtp inet n - - - 1 postscreen #smtpd pass - - - - - smtpd #dnsblog unix - - - - 0 dnsblog #tlsproxy unix - - - - 0 tlsproxy #submission inet n - - - - smtpd # -o smtpd_tls_security_level=encrypt # -o smtpd_sasl_auth_enable=yes # -o smtpd_client_restrictions=permit_sasl_authenticated,reject # -o milter_macro_daemon_name=ORIGINATING #smtps inet n - - - - smtpd # -o smtpd_tls_wrappermode=yes # -o smtpd_sasl_auth_enable=yes # -o smtpd_client_restrictions=permit_sasl_authenticated,reject # -o milter_macro_daemon_name=ORIGINATING #628 inet n - - - - qmqpd pickup fifo n - - 60 1 pickup cleanup unix n - - - 0 cleanup qmgr fifo n - n 300 1 qmgr #qmgr fifo n - - 300 1 oqmgr tlsmgr unix - - - 1000? 1 tlsmgr rewrite unix - - - - - trivial-rewrite bounce unix - - - - 0 bounce defer unix - - - - 0 bounce trace unix - - - - 0 bounce verify unix - - - - 1 verify flush unix n - - 1000? 0 flush proxymap unix - - n - - proxymap proxywrite unix - - n - 1 proxymap smtp unix - - - - - smtp # When relaying mail as backup MX, disable fallback_relay to avoid MX loops relay unix - - - - - smtp -o smtp_fallback_relay= # -o smtp_helo_timeout=5 -o smtp_connect_timeout=5 showq unix n - - - - showq error unix - - - - - error retry unix - - - - - error discard unix - - - - - discard local unix - n n - - local virtual unix - n n - - virtual lmtp unix - - - - - lmtp anvil unix - - - - 1 anvil scache unix - - - - 1 scache # # ==================================================================== # Interfaces to non-Postfix software. Be sure to examine the manual # pages of the non-Postfix software to find out what options it wants. # # Many of the following services use the Postfix pipe(8) delivery # agent. See the pipe(8) man page for information about ${recipient} # and other message envelope options. # ==================================================================== # # maildrop. See the Postfix MAILDROP_README file for details. # Also specify in main.cf: maildrop_destination_recipient_limit=1 # maildrop unix - n n - - pipe flags=DRhu user=vmail argv=/usr/bin/maildrop -d ${recipient} # # ==================================================================== # # Recent Cyrus versions can use the existing "lmtp" master.cf entry. # # Specify in cyrus.conf: # lmtp cmd="lmtpd -a" listen="localhost:lmtp" proto=tcp4 # # Specify in main.cf one or more of the following: # mailbox_transport = lmtp:inet:localhost # virtual_transport = lmtp:inet:localhost # # ==================================================================== # # Cyrus 2.1.5 (Amos Gouaux) # Also specify in main.cf: cyrus_destination_recipient_limit=1 # #cyrus unix - n n - - pipe # user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user} # # ==================================================================== # Old example of delivery via Cyrus. # #old-cyrus unix - n n - - pipe # flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user} # # ==================================================================== # # See the Postfix UUCP_README file for configuration details. # uucp unix - n n - - pipe flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient) # # Other external delivery methods. # ifmail unix - n n - - pipe flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient) bsmtp unix - n n - - pipe flags=Fq. user=bsmtp argv=/usr/lib/bsmtp/bsmtp -t$nexthop -f$sender $recipient scalemail-backend unix - n n - 2 pipe flags=R user=scalemail argv=/usr/lib/scalemail/bin/scalemail-store ${nexthop} ${user} ${extension} mailman unix - n n - - pipe flags=FR user=list argv=/usr/lib/mailman/bin/postfix-to-mailman.py ${nexthop} ${user} dovecot unix - n n - - pipe flags=DRhu user=vmail:vmail argv=/usr/lib/dovecot/deliver -d ${recipient}

  Read the article

• Load and Web Performance Testing using Visual Studio Ultimate 2010-Part 3

  - by Tarun Arora

  Welcome back once again, in Part 1 of Load and Web Performance Testing using Visual Studio 2010 I talked about why Performance Testing the application is important, the test tools available in Visual Studio Ultimate 2010 and various test rig topologies, in Part 2 of Load and Web Performance Testing using Visual Studio 2010 I discussed the details of web performance & load tests as well as why it’s important to follow a goal based pattern while performance testing your application. In part 3 I’ll be discussing Test Result Analysis, Test Result Drill through, Test Report Generation, Test Run Comparison, Asp.net Profiler and some closing thoughts. Test Results – I see some creepy worms! In Part 2 we put together a web performance test and a load test, lets run the test to see load test to see how the Web site responds to the load simulation. While the load test is running you will be able to see close to real time analysis in the Load Test Analyser window. You can use the Load Test Analyser to conduct load test analysis in three ways: Monitor a running load test - A condensed set of the performance counter data is maintained in memory. To prevent the results memory requirements from growing unbounded, up to 200 samples for each performance counter are maintained. This includes 100 evenly spaced samples that span the current elapsed time of the run and the most recent 100 samples.         After the load test run is completed - The test controller spools all collected performance counter data to a database while the test is running. Additional data, such as timing details and error details, is loaded into the database when the test completes. The performance data for a completed test is loaded from the database and analysed by the Load Test Analyser. Below you can see a screen shot of the summary view, this provides key results in a format that is compact and easy to read. You can also print the load test summary, this is generated after the test has completed or been stopped.         Analyse the load test results of a previously run load test – We’ll see this in the section where i discuss comparison between two test runs. The performance counters can be plotted on the graphs. You also have the option to highlight a selected part of the test and view details, drill down to the user activity chart where you can hover over to see more details of the test run.   Generate Report => Test Run Comparisons The level of reports you can generate using the Load Test Analyser is astonishing. You have the option to create excel reports and conduct side by side analysis of two test results or to track trend analysis. The tools also allows you to export the graph data either to MS Excel or to a CSV file. You can view the ASP.NET profiler report to conduct further analysis as well. View Data and Diagnostic Attachments opens the Choose Diagnostic Data Adapter Attachment dialog box to select an adapter to analyse the result type. For example, you can select an IntelliTrace adapter, click OK and open the IntelliTrace summary for the test agent that was used in the load test.   Compare results This creates a set of reports that compares the data from two load test results using tables and bar charts. I have taken these screen shots from the MSDN documentation, I would highly recommend exploring the wealth of knowledge available on MSDN. Leaving Thoughts While load testing the application with an excessive load for a longer duration of time, i managed to bring the IIS to its knees by piling up a huge queue of requests waiting to be processed. This clearly means that the IIS had run out of threads as all the threads were busy processing existing request, one easy way of fixing this is by increasing the default number of allocated threads, but this might escalate the problem. The better suggestion is to try and drill down to the actual root cause of the problem. When ever the garbage collection runs it stops processing any pages so all requests that come in during that period are queued up, but realistically the garbage collection completes in fraction of a a second. To understand this better lets look at the .net heap, it is divided into large heap and small heap, anything greater than 85kB in size will be allocated to the Large object heap, the Large object heap is non compacting and remember large objects are expensive to move around, so if you are allocating something in the large object heap, make sure that you really need it! The small object heap on the other hand is divided into generations, so all objects that are supposed to be short-lived are suppose to live in Gen-0 and the long living objects eventually move to Gen-2 as garbage collection goes through.  As you can see in the picture below all < 85 KB size objects are first assigned to Gen-0, when Gen-0 fills up and a new object comes in and finds Gen-0 full, the garbage collection process is started, the process checks for all the dead objects and assigns them as the valid candidate for deletion to free up memory and promotes all the remaining objects in Gen-0 to Gen-1. So in the future when ever you clean up Gen-1 you have to clean up Gen-0 as well. When you fill up Gen – 0 again, all of Gen – 1 dead objects are drenched and rest are moved to Gen-2 and Gen-0 objects are moved to Gen-1 to free up Gen-0, but by this time your Garbage collection process has started to take much more time than it usually takes. Now as I mentioned earlier when garbage collection is being run all page requests that come in during that period are queued up. Does this explain why possibly page requests are getting queued up, apart from this it could also be the case that you are waiting for a long running database process to complete.      Lets explore the heap a bit more… What is really a case of crisis is when the objects are living long enough to make it to Gen-2 and then dying, this is definitely a high cost operation. But sometimes you need objects in memory, for example when you cache data you hold on to the objects because you need to use them right across the user session, which is acceptable. But if you wanted to see what extreme caching can do to your server then write a simple application that chucks in a lot of data in cache, run a load test over it for about 10-15 minutes, forcing a lot of data in memory causing the heap to run out of memory. If you get to such a state where you start running out of memory the IIS as a mode of recovery restarts the worker process. It is great way to free up all your memory in the heap but this would clear the cache. The problem with this is if the customer had 10 items in their shopping basket and that data was stored in the application cache, the user basket will now be empty forcing them either to get frustrated and go to a competitor website or if the customer is really patient, give it another try! How can you address this, well two ways of addressing this; 1. Workaround – A x86 bit processor only allows a maximum of 4GB of RAM, this means the machine effectively has around 3.4 GB of RAM available, the OS needs about 1.5 GB of RAM to run efficiently, the IIS and .net framework also need their share of memory, leaving you a heap of around 800 MB to play with. Because Team builds by default build your application in ‘Compile as any mode’ it means the application is build such that it will run in x86 bit mode if run on a x86 bit processor and run in a x64 bit mode if run on a x64 but processor. The problem with this is not all applications are really x64 bit compatible specially if you are using com objects or external libraries. So, as a quick win if you compiled your application in x86 bit mode by changing the compile as any selection to compile as x86 in the team build, you will be able to run your application on a x64 bit machine in x86 bit mode (WOW – By running Windows on Windows) and what that means is, you could use 8GB+ worth of RAM, if you take away everything else your application will roughly get a heap size of at least 4 GB to play with, which is immense. If you need a heap size of more than 4 GB you have either build a software for NASA or there is something fundamentally wrong in your application. 2. Solution – Now that you have put a workaround in place the IIS will not restart the worker process that regularly, which means you can take a breather and start working to get to the root cause of this memory leak. But this begs a question “How do I Identify possible memory leaks in my application?” Well i won’t say that there is one single tool that can tell you where the memory leak is, but trust me, ‘Performance Profiling’ is a great start point, it definitely gets you started in the right direction, let’s have a look at how. Performance Wizard - Start the Performance Wizard and select Instrumentation, this lets you measure function call counts and timings. Before running the performance session right click the performance session settings and chose properties from the context menu to bring up the Performance session properties page and as shown in the screen shot below, check the check boxes in the group ‘.NET memory profiling collection’ namely ‘Collect .NET object allocation information’ and ‘Also collect the .NET Object lifetime information’.    Now if you fire off the profiling session on your pages you will notice that the results allows you to view ‘Object Lifetime’ which shows you the number of objects that made it to Gen-0, Gen-1, Gen-2, Large heap, etc. Another great feature about the profile is that if your application has > 5% cases where objects die right after making to the Gen-2 storage a threshold alert is generated to alert you. Since you have the option to also view the most expensive methods and by capturing the IntelliTrace data you can drill in to narrow down to the line of code that is the root cause of the problem. Well now that we have seen how crucial memory management is and how easy Visual Studio Ultimate 2010 makes it for us to identify and reproduce the problem with the best of breed tools in the product. Caching One of the main ways to improve performance is Caching. Which basically means you tell the web server that instead of going to the database for each request you keep the data in the webserver and when the user asks for it you serve it from the webserver itself. BUT that can have consequences! Let’s look at some code, trust me caching code is not very intuitive, I define a cache key for almost all searches made through the common search page and cache the results. The approach works fine, first time i get the data from the database and second time data is served from the cache, significant performance improvement, EXCEPT when two users try to do the same operation and run into each other. But it is easy to handle this by adding the lock as you can see in the snippet below. So, as long as a user comes in and finds that the cache is empty, the user locks and starts to get the cache no more concurrency issues. But lets say you are processing 10 requests per second, by the time i have locked the operation to get the results from the database, 9 other users came in and found that the cache key is null so after i have come out and populated the cache they will still go in to get the results again. The application will still be faster because the next set of 10 users and so on would continue to get data from the cache. BUT if we added another null check after locking to build the cache and before actual call to the db then the 9 users who follow me would not make the extra trip to the database at all and that would really increase the performance, but didn’t i say that the code won’t be very intuitive, may be you should leave a comment you don’t want another developer to come in and think what a fresher why is he checking for the cache key null twice !!! The downside of caching is, you are storing the data outside of the database and the data could be wrong because the updates applied to the database would make the data cached at the web server out of sync. So, how do you invalidate the cache? Well if you only had one way of updating the data lets say only one entry point to the data update you can write some logic to say that every time new data is entered set the cache object to null. But this approach will not work as soon as you have several ways of feeding data to the system or your system is scaled out across a farm of web servers. The perfect solution to this is Micro Caching which means you cache the query for a set time duration and invalidate the cache after that set duration. The advantage is every time the user queries for that data with in the time span for which you have cached the results there are no calls made to the database and the data is served right from the server which makes the response immensely quick. Now figuring out the appropriate time span for which you micro cache the query results really depends on the application. Lets say your website gets 10 requests per second, if you retain the cache results for even 1 minute you will have immense performance gains. You would reduce 90% hits to the database for searching. Ever wondered why when you go to e-bookers.com or xpedia.com or yatra.com to book a flight and you click on the book button because the fare seems too exciting and you get an error message telling you that the fare is not valid any more. Yes, exactly => That is a cache failure! These travel sites or price compare engines are not going to hit the database every time you hit the compare button instead the results will be served from the cache, because the query results are micro cached, its a perfect trade-off, by micro caching the results the site gains 100% performance benefits but every once in a while annoys a customer because the fare has expired. But the trade off works in the favour of these sites as they are still able to process up to 30+ page requests per second which means cater to the site traffic by may be losing 1 customer every once in a while to a competitor who is also using a similar caching technique what are the odds that the user will not come back to their site sooner or later? Recap   Resources Below are some Key resource you might like to review. I would highly recommend the documentation, walkthroughs and videos available on MSDN. You can always make use of Fiddler to debug Web Performance Tests. Some community test extensions and plug ins available on Codeplex might also be of interest to you. The Road Ahead Thank you for taking the time out and reading this blog post, you may also want to read Part I and Part II if you haven’t so far. If you enjoyed the post, remember to subscribe to http://feeds.feedburner.com/TarunArora. Questions/Feedback/Suggestions, etc please leave a comment. Next ‘Load Testing in the cloud’, I’ll be working on exploring the possibilities of running Test controller/Agents in the Cloud. See you on the other side! Thank You!   Share this post : CodeProject

  Read the article

• 64-bit Archives Needed

  - by user9154181

  A little over a year ago, we received a question from someone who was trying to build software on Solaris. He was getting errors from the ar command when creating an archive. At that time, the ar command on Solaris was a 32-bit command. There was more than 2GB of data, and the ar command was hitting the file size limit for a 32-bit process that doesn't use the largefile APIs. Even in 2011, 2GB is a very large amount of code, so we had not heard this one before. Most of our toolchain was extended to handle 64-bit sized data back in the 1990's, but archives were not changed, presumably because there was no perceived need for it. Since then of course, programs have continued to get larger, and in 2010, the time had finally come to investigate the issue and find a way to provide for larger archives. As part of that process, I had to do a deep dive into the archive format, and also do some Unix archeology. I'm going to record what I learned here, to document what Solaris does, and in the hope that it might help someone else trying to solve the same problem for their platform. Archive Format Details Archives are hardly cutting edge technology. They are still used of course, but their basic form hasn't changed in decades. Other than to fix a bug, which is rare, we don't tend to touch that code much. The archive file format is described in /usr/include/ar.h, and I won't repeat the details here. Instead, here is a rough overview of the archive file format, implemented by System V Release 4 (SVR4) Unix systems such as Solaris: Every archive starts with a "magic number". This is a sequence of 8 characters: "!<arch>\n". The magic number is followed by 1 or more members. A member starts with a fixed header, defined by the ar_hdr structure in/usr/include/ar.h. Immediately following the header comes the data for the member. Members must be padded at the end with newline characters so that they have even length. The requirement to pad members to an even length is a dead giveaway as to the age of the archive format. It tells you that this format dates from the 1970's, and more specifically from the era of 16-bit systems such as the PDP-11 that Unix was originally developed on. A 32-bit system would have required 4 bytes, and 64-bit systems such as we use today would probably have required 8 bytes. 2 byte alignment is a poor choice for ELF object archive members. 32-bit objects require 4 byte alignment, and 64-bit objects require 64-bit alignment. The link-editor uses mmap() to process archives, and if the members have the wrong alignment, we have to slide (copy) them to the correct alignment before we can access the ELF data structures inside. The archive format requires 2 byte padding, but it doesn't prohibit more. The Solaris ar command takes advantage of this, and pads ELF object members to 8 byte boundaries. Anything else is padded to 2 as required by the format. The archive header (ar_hdr) represents all numeric values using an ASCII text representation rather than as binary integers. This means that an archive that contains only text members can be viewed using tools such as cat, more, or a text editor. The original designers of this format clearly thought that archives would be used for many file types, and not just for objects. Things didn't turn out that way of course — nearly all archives contain relocatable objects for a single operating system and machine, and are used primarily as input to the link-editor (ld). Archives can have special members that are created by the ar command rather than being supplied by the user. These special members are all distinguished by having a name that starts with the slash (/) character. This is an unambiguous marker that says that the user could not have supplied it. The reason for this is that regular archive members are given the plain name of the file that was inserted to create them, and any path components are stripped off. Slash is the delimiter character used by Unix to separate path components, and as such cannot occur within a plain file name. The ar command hides the special members from you when you list the contents of an archive, so most users don't know that they exist. There are only two possible special members: A symbol table that maps ELF symbols to the object archive member that provides it, and a string table used to hold member names that exceed 15 characters. The '/' convention for tagging special members provides room for adding more such members should the need arise. As I will discuss below, we took advantage of this fact to add an alternate 64-bit symbol table special member which is used in archives that are larger than 4GB. When an archive contains ELF object members, the ar command builds a special archive member known as the symbol table that maps all ELF symbols in the object to the archive member that provides it. The link-editor uses this symbol table to determine which symbols are provided by the objects in that archive. If an archive has a symbol table, it will always be the first member in the archive, immediately following the magic number. Unlike member headers, symbol tables do use binary integers to represent offsets. These integers are always stored in big-endian format, even on a little endian host such as x86. The archive header (ar_hdr) provides 15 characters for representing the member name. If any member has a name that is longer than this, then the real name is written into a special archive member called the string table, and the member's name field instead contains a slash (/) character followed by a decimal representation of the offset of the real name within the string table. The string table is required to precede all normal archive members, so it will be the second member if the archive contains a symbol table, and the first member otherwise. The archive format is not designed to make finding a given member easy. Such operations move through the archive from front to back examining each member in turn, and run in O(n) time. This would be bad if archives were commonly used in that manner, but in general, they are not. Typically, the ar command is used to build an new archive from scratch, inserting all the objects in one operation, and then the link-editor accesses the members in the archive in constant time by using the offsets provided by the symbol table. Both of these operations are reasonably efficient. However, listing the contents of a large archive with the ar command can be rather slow. Factors That Limit Solaris Archive Size As is often the case, there was more than one limiting factor preventing Solaris archives from growing beyond the 32-bit limits of 2GB (32-bit signed) and 4GB (32-bit unsigned). These limits are listed in the order they are hit as archive size grows, so the earlier ones mask those that follow. The original Solaris archive file format can handle sizes up to 4GB without issue. However, the ar command was delivered as a 32-bit executable that did not use the largefile APIs. As such, the ar command itself could not create a file larger than 2GB. One can solve this by building ar with the largefile APIs which would allow it to reach 4GB, but a simpler and better answer is to deliver a 64-bit ar, which has the ability to scale well past 4GB. Symbol table offsets are stored as 32-bit big-endian binary integers, which limits the maximum archive size to 4GB. To get around this limit requires a different symbol table format, or an extension mechanism to the current one, similar in nature to the way member names longer than 15 characters are handled in member headers. The size field in the archive member header (ar_hdr) is an ASCII string capable of representing a 32-bit unsigned value. This places a 4GB size limit on the size of any individual member in an archive. In considering format extensions to get past these limits, it is important to remember that very few archives will require the ability to scale past 4GB for many years. The old format, while no beauty, continues to be sufficient for its purpose. This argues for a backward compatible fix that allows newer versions of Solaris to produce archives that are compatible with older versions of the system unless the size of the archive exceeds 4GB. Archive Format Differences Among Unix Variants While considering how to extend Solaris archives to scale to 64-bits, I wanted to know how similar archives from other Unix systems are to those produced by Solaris, and whether they had already solved the 64-bit issue. I've successfully moved archives between different Unix systems before with good luck, so I knew that there was some commonality. If it turned out that there was already a viable defacto standard for 64-bit archives, it would obviously be better to adopt that rather than invent something new. The archive file format is not formally standardized. However, the ar command and archive format were part of the original Unix from Bell Labs. Other systems started with that format, extending it in various often incompatible ways, but usually with the same common shared core. Most of these systems use the same magic number to identify their archives, despite the fact that their archives are not always fully compatible with each other. It is often true that archives can be copied between different Unix variants, and if the member names are short enough, the ar command from one system can often read archives produced on another. In practice, it is rare to find an archive containing anything other than objects for a single operating system and machine type. Such an archive is only of use on the type of system that created it, and is only used on that system. This is probably why cross platform compatibility of archives between Unix variants has never been an issue. Otherwise, the use of the same magic number in archives with incompatible formats would be a problem. I was able to find information for a number of Unix variants, described below. These can be divided roughly into three tribes, SVR4 Unix, BSD Unix, and IBM AIX. Solaris is a SVR4 Unix, and its archives are completely compatible with those from the other members of that group (GNU/Linux, HP-UX, and SGI IRIX). AIX AIX is an exception to rule that Unix archive formats are all based on the original Bell labs Unix format. It appears that AIX supports 2 formats (small and big), both of which differ in fundamental ways from other Unix systems: These formats use a different magic number than the standard one used by Solaris and other Unix variants. They include support for removing archive members from a file without reallocating the file, marking dead areas as unused, and reusing them when new archive items are inserted. They have a special table of contents member (File Member Header) which lets you find out everything that's in the archive without having to actually traverse the entire file. Their symbol table members are quite similar to those from other systems though. Their member headers are doubly linked, containing offsets to both the previous and next members. Of the Unix systems described here, AIX has the only format I saw that will have reasonable insert/delete performance for really large archives. Everyone else has O(n) performance, and are going to be slow to use with large archives. BSD BSD has gone through 4 versions of archive format, which are described in their manpage. They use the same member header as SVR4, but their symbol table format is different, and their scheme for long member names puts the name directly after the member header rather than into a string table. GNU/Linux The GNU toolchain uses the SVR4 format, and is compatible with Solaris. HP-UX HP-UX seems to follow the SVR4 model, and is compatible with Solaris. IRIX IRIX has 32 and 64-bit archives. The 32-bit format is the standard SVR4 format, and is compatible with Solaris. The 64-bit format is the same, except that the symbol table uses 64-bit integers. IRIX assumes that an archive contains objects of a single ELFCLASS/MACHINE, and any archive containing ELFCLASS64 objects receives a 64-bit symbol table. Although they only use it for 64-bit objects, nothing in the archive format limits it to ELFCLASS64. It would be perfectly valid to produce a 64-bit symbol table in an archive containing 32-bit objects, text files, or anything else. Tru64 Unix (Digital/Compaq/HP) Tru64 Unix uses a format much like ours, but their symbol table is a hash table, making specific symbol lookup much faster. The Solaris link-editor uses archives by examining the entire symbol table looking for unsatisfied symbols for the link, and not by looking up individual symbols, so there would be no benefit to Solaris from such a hash table. The Tru64 ld must use a different approach in which the hash table pays off for them. Widening the existing SVR4 archive symbol tables rather than inventing something new is the simplest path forward. There is ample precedent for this approach in the ELF world. When ELF was extended to support 64-bit objects, the approach was largely to take the existing data structures, and define 64-bit versions of them. We called the old set ELF32, and the new set ELF64. My guess is that there was no need to widen the archive format at that time, but had there been, it seems obvious that this is how it would have been done. The Implementation of 64-bit Solaris Archives As mentioned earlier, there was no desire to improve the fundamental nature of archives. They have always had O(n) insert/delete behavior, and for the most part it hasn't mattered. AIX made efforts to improve this, but those efforts did not find widespread adoption. For the purposes of link-editing, which is essentially the only thing that archives are used for, the existing format is adequate, and issues of backward compatibility trump the desire to do something technically better. Widening the existing symbol table format to 64-bits is therefore the obvious way to proceed. For Solaris 11, I implemented that, and I also updated the ar command so that a 64-bit version is run by default. This eliminates the 2 most significant limits to archive size, leaving only the limit on an individual archive member. We only generate a 64-bit symbol table if the archive exceeds 4GB, or when the new -S option to the ar command is used. This maximizes backward compatibility, as an archive produced by Solaris 11 is highly likely to be less than 4GB in size, and will therefore employ the same format understood by older versions of the system. The main reason for the existence of the -S option is to allow us to test the 64-bit format without having to construct huge archives to do so. I don't believe it will find much use outside of that. Other than the new ability to create and use extremely large archives, this change is largely invisible to the end user. When reading an archive, the ar command will transparently accept either form of symbol table. Similarly, the ELF library (libelf) has been updated to understand either format. Users of libelf (such as the link-editor ld) do not need to be modified to use the new format, because these changes are encapsulated behind the existing functions provided by libelf. As mentioned above, this work did not lift the limit on the maximum size of an individual archive member. That limit remains fixed at 4GB for now. This is not because we think objects will never get that large, for the history of computing says otherwise. Rather, this is based on an estimation that single relocatable objects of that size will not appear for a decade or two. A lot can change in that time, and it is better not to overengineer things by writing code that will sit and rot for years without being used. It is not too soon however to have a plan for that eventuality. When the time comes when this limit needs to be lifted, I believe that there is a simple solution that is consistent with the existing format. The archive member header size field is an ASCII string, like the name, and as such, the overflow scheme used for long names can also be used to handle the size. The size string would be placed into the archive string table, and its offset in the string table would then be written into the archive header size field using the same format "/ddd" used for overflowed names.

  Read the article

• F# Objects &ndash; Part 3 &ndash; it&rsquo;s time to overload&hellip;

  - by MarkPearl

  Okay, some basic examples of overloading in F# Overloading Constructors Assume you have a F# object called person… type Person (firstname : string, lastname : string) = member v.Fullname = firstname + " " + lastname   This only has one constructor. To add additional constructors to the object by explicitly declaring them using the method member new. type Person (firstname : string, lastname : string) = new () = Person("Unknown", "Unknown") member v.Fullname = firstname + " " + lastname   In the code above I added another constructor to the Person object that takes no parameters and then refers to the primary constructor. Using the same technique in the code below I have created another constructor that accepts only the firstname as a parameter to create an object. type Person (firstname : string, lastname : string) = new () = Person("Unknown", "Unknown") new (firstname : string) = Person(firstname, "Unknown") member v.Fullname = firstname + " " + lastname   Overloading Operators So, you can overload operators of objects in F# as well… let’s look at example code… type Person(name : string) = member v.name = name static member (+) (person1 : Person , person2 : Person) = Person(person1.name + " " + person2.name)   In the code above we have overloaded the “+” operator. Whenever we add to Person objects together, it will now create a new object with the combined names…

  Read the article

• Microsoft Entourage/Exchange Server problem: all objects disappeared from server - still in some form on the client

  - by splattne

  One of our employees works with Entourage on his MacBook Pro (OSX 10.6) accessing Exchange Server 2007. Last Friday morning, I think while working over a VPN, Entourage (I think it was Entourage) deleted all his objects (mail, calendar, contacts) on the server and while creating a lot of strange folders (starting with underscores) on the client. The local data seems to be there, but not in a consistent form. Since the user's mailbox is rather big, I suspect, that there was some kind of "move" operation which did not complete. I tried to export the data, but the export stops because of a corrupted object. Is there a tool or another way to export or retrieve the local data? Edit - FYI: we solved the problem getting his data from the previous night's backup.

  Read the article

• Why should I use Firewall Zones and not just Address Objects?

  - by SRobertJames

  I appreciate Firewall Address Objects and Address Groups - they simplify management by letting me give a name to a group of addresses. But I don't understand what Firewall Zones (LAN, WAN, DMZ, etc.) do for me over Address Groups. I know all firewalls have them, so there must be a good reason. But what do I gain by stating a rule applies to all traffic from LAN Zone to WAN Zone which comes from LAN Address Group to WAN Address Group? Why not just mention the Address Groups?

  Read the article

• How do I update the memberOf attributes of existing objects after adding the OpenLDAP Reverse Group Membership Maintenance overlay?

  - by mss

  This is a follow-up to this question: I added the memberof overlay to an existing OpenLDAP 2.4 server. Now I want to update the existing user objects. For new group memberships, the memberOf attribute is updated correctly. But I have a bunch of existing groups which aren't updated automatically. I could remove all users from their groups and re-add them to make sure these entries are in sync. Since this is a Univention Corporate Server which does a lot of magic when you modify the LDAP, I don't want to risk breaking my directory. Is there a way to trick the overlay to update these operational attributes?

  Read the article

• fast similarity detection

  - by reinierpost

  I have a large collection of objects and I need to figure out the similarities between them. To be exact: given two objects I can compute their dissimilarity as a number, a metric - higher values mean less similarity and 0 means the objects have identical contents. The cost of computing this number is proportional to the size of the smaller object (each object has a given size). I need the ability to quickly find, given an object, the set of objects similar to it. To be exact: I need to produce a data structure that maps any object o to the set of objects no more dissimilar to o than d, for some dissimilarity value d, such that listing the objects in the set takes no more time than if they were in an array or linked list (and perhaps they actually are). Typically, the set will be very much smaller than the total number of objects, so it is really worthwhile to perform this computation. It's good enough if the data structure assumes a fixed d, but if it works for an arbitrary d, even better. Have you seen this problem before, or something similar to it? What is a good solution? To be exact: a straightforward solution involves computing the dissimilarities between all pairs of objects, but this is slow - O(n2) where n is the number of objects. Is there a general solution with lower complexity?

  Read the article

• How to set up single array or dictionary for use in multiple datasources?

  - by Roman

  I have multiple TableViewDatasources that need to display list of objects form same pool depending of certain property. E.g. object.flag1 is set- it will show up in TableView1 object.flag2 is set- it will show up in TableView2 The obvious way would be to have separate arrays for each TableView, But same object may appear in different arrays. Also I need to update objects very often or access all objects through same array. How do I setup a single dictionary or array to have all objects in one structure? To put it in another way: When table view or selection changes, application need to redraw TableViews with the new data. Application have to access the pool of objects and search through them using iterator and accessing each object and its properties. I think that this is an expensive operation and want to avoid that. Perhaps maybe by making a global pool of objects a dictionary and exposing objects properties as dictionary fields. So instead of iterating global pool of objects I could access global pool Dicitonary in a manner of database by selecting objects that has fields that match particular criteria. Anyone know any example of doing that?

  Read the article

• Attributes in XML subtree that belong to the parent

  - by Bart van Heukelom

  Say I have this XML <doc:document> <objects> <circle radius="10" doc:colour="red" /> <circle radius="20" doc:colour="blue" /> </objects> </doc:document> And this is how it is parsed (pseudo code): // class DocumentParser public Document parse(Element edoc) { doc = new Document(); doc.objects = ObjectsParser.parse(edoc.getChild("objects")); for ( ...?... ) { doc.objectColours.put(object, colour); } return doc; } ObjectsParser is responsible for parsing the objects bit, but is not and should not be aware of the existence of documents. However, in Document colours are associated with objects by use of a Map. What kind of pattern would you recommend to give the colour settings back to DocumentParser.parse from ObjectsParser.parse so it can associate it with the objects they belong to in a map? The alternative would be something like this: <doc:document> <objects> <circle id="1938" radius="10" /> <circle id="6398" radius="20" /> </objects> <doc:objectViewSettings> <doc:objectViewSetting object="1938" colour="red" /> <doc:objectViewSetting object="6398" colour="blue" /> </doc:objectViewSettings> </doc:document> Ugly!

  Read the article

• Optimizing T-SQL where an array would be nice

  - by Polatrite

  Alright, first you'll need to grab a barf bag. I've been tasked with optimizing several old stored procedures in our database. This SP does the following: 1) cursor loops through a series of "buildings" 2) cursor loops through a week, Sunday-Saturday 3) has a huge set of IF blocks that are responsible for counting how many Objects of what Types are present in a given building Essentially what you'll see in this code block is that, if there are 5 objects of type #2, it will increment @Type_2_Objects_5 by 1. IF @Number_Type_1_Objects = 0 BEGIN SET @Type_1_Objects_0 = @Type_1_Objects_0 + 1 END IF @Number_Type_1_Objects = 1 BEGIN SET @Type_1_Objects_1 = @Type_1_Objects_1 + 1 END IF @Number_Type_1_Objects = 2 BEGIN SET @Type_1_Objects_2 = @Type_1_Objects_2 + 1 END IF @Number_Type_1_Objects = 3 BEGIN SET @Type_1_Objects_3 = @Type_1_Objects_3 + 1 END [... Objects_4 through Objects_20 for Type_1] IF @Number_Type_2_Objects = 0 BEGIN SET @Type_2_Objects_0 = @Type_2_Objects_0 + 1 END IF @Number_Type_2_Objects = 1 BEGIN SET @Type_2_Objects_1 = @Type_2_Objects_1 + 1 END IF @Number_Type_2_Objects = 2 BEGIN SET @Type_2_Objects_2 = @Type_2_Objects_2 + 1 END IF @Number_Type_2_Objects = 3 BEGIN SET @Type_2_Objects_3 = @Type_2_Objects_3 + 1 END [... Objects_4 through Objects_20 for Type_2] In addition to being extremely hacky (and limited to a quantity of 20 objects), it seems like a terrible way of handling this. In a traditional language, this could easily be solved with a 2-dimensional array... objects[type][quantity] += 1; I'm a T-SQL novice, but since writing stored procedures often uses a lot of temporary tables (which could essentially be a 2-dimensional array) I was wondering if someone could illuminate a better way of handling a situation like this with two dynamic pieces of data to store. Requested in comments: The columns are simply Number_Type_1_Objects, Number_Type_2_Objects, Number_Type_3_Objects, Number_Type_4_Objects, Number_Type_5_Objects, and CurrentDateTime. Each row in the table represents 5 minutes. The expected output is to figure out what percentage of time a given quantity of objects is present throughout each day. Sunday - Object Type 1 0 objects - 69 rows, 5:45, 34.85% 1 object - 85 rows, 7:05, 42.93% 2 objects - 44 rows, 3:40, 22.22% On Sunday, there were 0 objects of type 1 for 34.85% of the day. There was 1 object for 42.93% of the day, and 2 objects for 22.22% of the day. Repeat for each object type.

  Read the article

• Collision filtering by object, team

  - by Bill Zimmerman

  Hi, I am looking for a good method to determine which objects will be considered for collision with other objects. My current idea is that each object has the following properties: alwaysCollidesWith = [list of objects that will always trigger a collision check] neverCollidesWith = [lost of objects that will never be considered] teamCollidesWith = [list of objects that will be checked, provided they belong to a different team] For example: -projectiles never have to be checked for collisions with other projectiles -players are always checked for collisions with players, regardless of team -projectiles are only considered for collisions if they collide with another teams players Does anyone see any weaknesses with this approach? Can anyone recommend a better approach?

  Read the article

• Newton Game Dynamics: Making an object not affect another object

  - by Boreal

  I'm going to be using Newton in my networked action game with Mogre. There will be two "types" of physics object: global and local. Global objects will be kept in sync for everybody; these include the players, projectiles, and other gameplay-related objects. Local objects are purely for effect, like ragdolls, debris, and particles. Is there a way to make the global objects affect the local objects without actually getting affected themselves? I'd like debris to bounce off of a tank, but I don't want the tank to respond in any way.

  Read the article

• 3D Location Handling

  - by tgrosinger

  I am thinking about making a simulator type game that will involve having lots of small objects in a 3D space. What is the typical solution for handling these objects? The first thing that comes to mind is a 3D Array, but I can't help but think there is a more efficient solution. Another idea that comes to mind is objects having possession of smaller items. For example a House possesses a Table which possesses a Cup and Bowl. The final way I can think of handling this is just having an array of "objects" that each have an x, y, z value. While this would make storing them easy I do not understand how you would detect collisions without just looking at every possible object and checking to see if it is in the way. Are there other ways of holding onto these objects that is more efficient?

  Read the article

• How to create an array of User Objects in Powerbuilder?

  - by TomatoSandwich

  The application has many different windows. One is a single 'row' window, which relates to a single row of data in a table, say 'Order'. Another is a 'multiple row' datawindow, where each row in the datawindow relates to a row in 'Order', used for spreadsheet-like data entry Functionality extentions have create a detail table, say 'Suppliers', where an order may require multiple suppliers to fill the order. Normally, suppliers are not required, because they are already in the warehouse (0), or there may need to be an order to a supplier to complete an order (1), or multiple suppliers may need to be contacted (more than one). As a single order is entered, once the items are entered, a User Object is populated depending on the status of the items in the warehouse. If required, this creates a 1-to-many relationship between the order and the "backorder". In the PB side, there is a single object uo_backorder which is created on the window, and is referenced by the window depending on the command (button popup, save, etc) I have been tasked to create the 'backorder' functionality on the spreadsheet-line window. Previously the default options for backorders were used when orders were created from the multiple-row window. A workaround already exists where unconfirmed orders could be opened in the single-row window, and the backorder information manipulated there. However, the userbase wants this functionality on the one window. Since the functionality of uo_backorder already exists, I assumed I could just copy the code from the single-order window, but create an array of uo_backorder objects to cope with multiple rows. I tried the following: forward .. type uo_backorder from popupdwpb within w_order_conv end type end forward global type w_order_conv from singleform .. uo_backorder uo_backorder end type type variables .. uo_backorder iuo_backorders[] end variables .. public function boolean iuo_backorders(); .. long ll_count ll_count = UpperBound(iuo_backorders[]) iuo_backorders[ll_count+1] = uo_backorder //THIS ISN'T RIGHT lb_ok = iuo_backorders[ll_count+1].init('w_backorder_popup', '', '', '', 'd_backorder_popup', sqlca, useTransObj()) return lb_ok end function .. <utility functions> .. type uo_backorder from popupdwpb within w_order_conv integer x = 28 integer y = 28 integer width ... end type on uo_backorder.destroy call popupdwpb::destroy end on The issue I face now is that the code commented "THIS ISN'T RIGHT" isn't correct. It is associating the visual object placed on the face of the main window to each array cell, so anytime I reference the array cell object it's actually referencing the one original object, not the new instances that I (thought) I was creating. If I change the code iuo_backorders[ll_count+1] = create uo_backorder the code doesn't run, saying that it failed to initalize the popup window. I think this is related to the class being called the same thing as the instance. What I want to end up with is an array of uo_backorder objects that I can associate to each row of my datawindow (first row = first cell, etc). I think the issue lays in the fact it's a visual object, and I can't seem to get the window to run without adding a dummy object on the face of the window (functionality from the original single-row window). Since it's a VISUAL object, does the object indeed need to be embedded on the windowface for the window to know what object I'm talking about? If so, how does one create multiple windowface objects (one to many, depending on when a row is added)? Don't hesitate to inquire regarding any more information this issue may require from myself. I have no idea what is 'standard' or 'default' in PB, or what is custom and needs more explaining.

  Read the article

< Previous Page | 88 89 90 91 92 93 94 95 96 97 98 99  | Next Page >