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  • Cisco ASA - Enable communication between same security level

    - by Conor
    I have recently inherited a network with a Cisco ASA (running version 8.2). I am trying to configure it to allow communication between two interfaces configured with the same security level (DMZ-DMZ) "same-security-traffic permit inter-interface" has been set, but hosts are unable to communicate between the interfaces. I am assuming that some NAT settings are causing my issue. Below is my running config: ASA Version 8.2(3) ! hostname asa enable password XXXXXXXX encrypted passwd XXXXXXXX encrypted names ! interface Ethernet0/0 switchport access vlan 400 ! interface Ethernet0/1 switchport access vlan 400 ! interface Ethernet0/2 switchport access vlan 420 ! interface Ethernet0/3 switchport access vlan 420 ! interface Ethernet0/4 switchport access vlan 450 ! interface Ethernet0/5 switchport access vlan 450 ! interface Ethernet0/6 switchport access vlan 500 ! interface Ethernet0/7 switchport access vlan 500 ! interface Vlan400 nameif outside security-level 0 ip address XX.XX.XX.10 255.255.255.248 ! interface Vlan420 nameif public security-level 20 ip address 192.168.20.1 255.255.255.0 ! interface Vlan450 nameif dmz security-level 50 ip address 192.168.10.1 255.255.255.0 ! interface Vlan500 nameif inside security-level 100 ip address 192.168.0.1 255.255.255.0 ! ftp mode passive clock timezone JST 9 same-security-traffic permit inter-interface same-security-traffic permit intra-interface object-group network DM_INLINE_NETWORK_1 network-object host XX.XX.XX.11 network-object host XX.XX.XX.13 object-group service ssh_2220 tcp port-object eq 2220 object-group service ssh_2251 tcp port-object eq 2251 object-group service ssh_2229 tcp port-object eq 2229 object-group service ssh_2210 tcp port-object eq 2210 object-group service DM_INLINE_TCP_1 tcp group-object ssh_2210 group-object ssh_2220 object-group service zabbix tcp port-object range 10050 10051 object-group service DM_INLINE_TCP_2 tcp port-object eq www group-object zabbix object-group protocol TCPUDP protocol-object udp protocol-object tcp object-group service http_8029 tcp port-object eq 8029 object-group network DM_INLINE_NETWORK_2 network-object host 192.168.20.10 network-object host 192.168.20.30 network-object host 192.168.20.60 object-group service imaps_993 tcp description Secure IMAP port-object eq 993 object-group service public_wifi_group description Service allowed on the Public Wifi Group. Allows Web and Email. service-object tcp-udp eq domain service-object tcp-udp eq www service-object tcp eq https service-object tcp-udp eq 993 service-object tcp eq imap4 service-object tcp eq 587 service-object tcp eq pop3 service-object tcp eq smtp access-list outside_access_in remark http traffic from outside access-list outside_access_in extended permit tcp any object-group DM_INLINE_NETWORK_1 eq www access-list outside_access_in remark ssh from outside to web1 access-list outside_access_in extended permit tcp any host XX.XX.XX.11 object-group ssh_2251 access-list outside_access_in remark ssh from outside to penguin access-list outside_access_in extended permit tcp any host XX.XX.XX.10 object-group ssh_2229 access-list outside_access_in remark http from outside to penguin access-list outside_access_in extended permit tcp any host XX.XX.XX.10 object-group http_8029 access-list outside_access_in remark ssh from outside to internal hosts access-list outside_access_in extended permit tcp any host XX.XX.XX.13 object-group DM_INLINE_TCP_1 access-list outside_access_in remark dns service to internal host access-list outside_access_in extended permit object-group TCPUDP any host XX.XX.XX.13 eq domain access-list dmz_access_in extended permit ip 192.168.10.0 255.255.255.0 any access-list dmz_access_in extended permit tcp any host 192.168.10.29 object-group DM_INLINE_TCP_2 access-list public_access_in remark Web access to DMZ websites access-list public_access_in extended permit object-group TCPUDP any object-group DM_INLINE_NETWORK_2 eq www access-list public_access_in remark General web access. (HTTP, DNS & ICMP and Email) access-list public_access_in extended permit object-group public_wifi_group any any pager lines 24 logging enable logging asdm informational mtu outside 1500 mtu public 1500 mtu dmz 1500 mtu inside 1500 no failover icmp unreachable rate-limit 1 burst-size 1 no asdm history enable arp timeout 60 global (outside) 1 interface global (dmz) 2 interface nat (public) 1 0.0.0.0 0.0.0.0 nat (dmz) 1 0.0.0.0 0.0.0.0 nat (inside) 1 0.0.0.0 0.0.0.0 static (inside,outside) tcp interface 2229 192.168.0.29 2229 netmask 255.255.255.255 static (inside,outside) tcp interface 8029 192.168.0.29 www netmask 255.255.255.255 static (dmz,outside) XX.XX.XX.13 192.168.10.10 netmask 255.255.255.255 dns static (dmz,outside) XX.XX.XX.11 192.168.10.30 netmask 255.255.255.255 dns static (dmz,inside) 192.168.0.29 192.168.10.29 netmask 255.255.255.255 static (dmz,public) 192.168.20.30 192.168.10.30 netmask 255.255.255.255 dns static (dmz,public) 192.168.20.10 192.168.10.10 netmask 255.255.255.255 dns static (inside,dmz) 192.168.10.0 192.168.0.0 netmask 255.255.255.0 dns access-group outside_access_in in interface outside access-group public_access_in in interface public access-group dmz_access_in in interface dmz route outside 0.0.0.0 0.0.0.0 XX.XX.XX.9 1 timeout xlate 3:00:00 timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02 timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00 timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00 timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute timeout tcp-proxy-reassembly 0:01:00 dynamic-access-policy-record DfltAccessPolicy http server enable http 192.168.0.0 255.255.255.0 inside no snmp-server location no snmp-server contact snmp-server enable traps snmp authentication linkup linkdown coldstart crypto ipsec security-association lifetime seconds 28800 crypto ipsec security-association lifetime kilobytes 4608000 telnet timeout 5 ssh 192.168.0.0 255.255.255.0 inside ssh timeout 20 console timeout 0 dhcpd dns 61.122.112.97 61.122.112.1 dhcpd auto_config outside ! dhcpd address 192.168.20.200-192.168.20.254 public dhcpd enable public ! dhcpd address 192.168.0.200-192.168.0.254 inside dhcpd enable inside ! threat-detection basic-threat threat-detection statistics host threat-detection statistics access-list no threat-detection statistics tcp-intercept ntp server 130.54.208.201 source public webvpn ! class-map inspection_default match default-inspection-traffic ! ! policy-map type inspect dns preset_dns_map parameters message-length maximum client auto message-length maximum 512 policy-map global_policy class inspection_default inspect dns preset_dns_map inspect ftp inspect h323 h225 inspect h323 ras inspect ip-options inspect netbios inspect rsh inspect rtsp inspect skinny inspect esmtp inspect sqlnet inspect sunrpc inspect tftp inspect sip inspect xdmcp !

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  • CodeContracts: ccrewrite fails with Object reference not set to an instance of an object

    - by Vyas Bharghava
    The below code makes ccrewrite blow up! Ideas? BTW, If you comment out the ActualClass, ccrewrite succeeds... [ContractClass(typeof(TestContracts))] interface ITestInterface { bool IsStarted { get; set; } void Begin(); } class ActualClass : ITestInterface { public bool IsStarted { get; set; } public void Begin() { this.IsStarted = true; } } [ContractClassFor(typeof(ITestInterface))] class TestContracts : ITestInterface { ITestInterface Current { get; set; } private TestContracts() { Current = this; } #region ITestInterface Members bool ITestInterface.IsStarted { get; set; } void ITestInterface.Begin() { Contract.Requires(!Current.IsStarted); Contract.Ensures(Current.IsStarted); } Thanks in advance!

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  • C# programatically using a string as object name when instantiating an object

    - by emk
    This is a contrived example, but lets say I have declared objects: CustomObj fooObj; CustomObj barObj; CustomObj bazObj; And I have an string array: string[] stringarray = new string[] {"foo","bar","baz"}; How can I programatically access and instantiate those objects using the string array, iterating using something like a foreach: foreach (string i in stringarray) { `i`Obj = new CustomObj(i); } Hope the idea I'm trying to get across is clear. Is this possible in C#? Thanks in advance.

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  • nHibernate query looking for the related object's related object

    - by code-zoop
    I have an nHibernate querie issue that looks quite straight forward, but I can't seem to get my head around it! I am creating some simple example classes to illustrate my problem: public class Car { public int Id { get; set; } public IList<Interior> InteriorParts { get; set; } } public class Interior { public int Id { get; set; } public InteriorProducer Producer { get; set; } } public class InteriorProducer { public int Id { get; set; } } Now to the query: I have the id of the InteriorProducer, but need to get a list of Cars where the interior have been produced by the interior producer. So in a simple, pseudo SQL, it looks something like this: select cars where car.InteriorParts.Producer.Id = Id I have a really hard time getting my head around this to create an nHibernate query. Any Ideas? Thanks

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  • Sort Grid Columns of mixed type in EXTJS Grid

    - by Amit
    Hello, I want to sort the extjs columns, I have the column type as float and from the server side i am getting values which can contain "-" value , now what happens the grid is displaying me the NaN value instead of - and the sort is not working anymore. My requirement is to create a custom sort which can sort first based on number and then sort based on string. Thanks to suggest as renderer also not works for me. My Json String is: {metaData:{"totalProperty":"total", "root":"records","fields":[{"header":"Part Number##false","name":"XJE010^VT-007!0","type":"string"},{"header":"Marketing Status##false","name":"STP716^VT-007!0","type":"string"},{"header":"Package##false","name":"XJE016^VT-007!0","type":"string"},{"header":"Automotive Grade##false","name":"STP472^VT-007!0","type":"string"},{"header":"VDSS##false","name":"XJG810^VT-007!0","type":"float"},{"header":"Drain Current (Dc)(I_D) % (A)##false","name":"XJG273^VT-006!0","type":"float"},{"header":"RDS(on) (@VGS=10V) % (&#937;)##false","name":"XJG640^VT-006!3","type":"float"},{"header":"Features##false","name":"GNP023^VT-007!0","type":"string"},{"header":"RDS(on) (@4.5 or 5V) % (&#937;)##false","name":"XJG640^VT-006!6","type":"float"},{"header":"RDS(on) (@2.7V) % (&#937;)##false","name":"XJG640^VT-006!7","type":"float"},{"header":"RDS(on) (@1.8V) % (&#937;)##false","name":"XJG640^VT-006!8","type":"float"},{"header":"Free Samples##false","name":"STP0881^VT-007!0","type":"string"},{"header":"Total Gate Charge(Qg) typ ()##true","name":"STP049^VT-002!0","type":"float"},{"header":"Total Power Dissipation(PD) % (W)##true","name":"XJG820^VT-006!0","type":"float"}]},"success":"true", "total":13,"records":[{"XJE010^VT-007!0":"STB80PF55$$/cn/analog/product/67164.jsp","STP716^VT-007!0":"Active","XJE016^VT-007!0":"D2PAK","STP472^VT-007!0":"_","XJG810^VT-007!0":"-55","XJG273^VT-006!0":"80","XJG640^VT-006!3":".018","GNP023^VT-007!0":"-","XJG640^VT-006!6":"-","XJG640^VT-006!7":"-","XJG640^VT-006!8":"-","STP0881^VT-007!0":"No","STP049^VT-002!0":"190","XJG820^VT-006!0":"300"},{"XJE010^VT-007!0":"STD10PF06$$/cn/analog/product/64543.jsp","STP716^VT-007!0":"Active","XJE016^VT-007!0":"IPAK TO-251 TO 252 DPAK","STP472^VT-007!0":"_","XJG810^VT-007!0":"-60","XJG273^VT-006!0":"-10","XJG640^VT-006!3":".2","GNP023^VT-007!0":"-","XJG640^VT-006!6":"-","XJG640^VT-006!7":"-","XJG640^VT-006!8":"-","STP0881^VT-007!0":"No ... Regards, Amit

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  • deleting object with template for int and object

    - by Yokhen
    Alright so Say I have a class with all its definition, bla bla bla... template <class DT> class Foo{ private: DT* _data; //other stuff; public: Foo(DT* data){ _data = data } virtual ~Foo(){ delete _data } //other methods }; And then I have in the main method: int main(){ int number = 12; Foo<anyRandomClass>* noPrimitiveDataObject = new Foo<anyRandomClass>(new anyRandomClass()); Foo<int>* intObject = new Foo<int>(number); delete noPrimitiveDataObject; //Everything goes just fine. delete intObject; //It messes up here, I think because primitive data types such as int are allocated in a different way. return 0; } My question is: What could I do to have both delete statements in the main method work just fine? P.S.: Although I have not actually compiled/tested this specific code, I have reviewed it extensively (as well as indented. You're welcome.), so if you find a mistake, please be nice. Thank you.

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  • release object of a return method object c

    - by Piero
    in run the app with the analyze build, and Xcode found me a lot of memory leak and there is one in particular that i don't know how solve here it is: - (UIView *) tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section { UIImageView *sectionImage = [[UIImageView alloc] init]; if (section == 0)sectionImage.image = [UIImage imageNamed:@"myImage.png"]; return sectionImage; } so my question is, how i can release this sectionImage? if is the return of the method? EDIT: i have another question, analyze give me another memory leak, i have this: .h @property (nonatomic, retain) NSIndexPath *directCellPath; .m @synthesize directCellPath = _directCellPath; - (id)init{ if ((self = [super initWithNibName:@"MyViewController" bundle:nil])) { self.directCellPath = [[NSIndexPath alloc] init]; } return self; } then in the code i use it and finally in the dealloc i do this: - (void)dealloc { [_directCellPath release]; [super dealloc]; } and give me a memory leak on this line: self.directCellPath = [[NSIndexPath alloc] init]; why if i have deallocated it in the dealloc?

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  • xml error: Object reference not set to an instance of an object after SelectSingleNode

    - by every_answer_gets_a_point
    here's my code: XmlDocument doc = new XmlDocument(); foreach (string c in colorList) { doc.Load(@"http://whoisxmlapi.com/whoisserver/WhoisService?domainName=" + c + @"&username=user&password=pass"); textBox1.Text += doc.SelectSingleNode("WhoisRecord/registrant/email").InnerText + ","; } for the second line of code (textbox1...) is generating this error what am i doing wrong?

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  • Convert Google results object (pure js) to Python object

    - by colwilson
    So I'm trying to use Google Map suggest API to request place name suggestions. Unfortunately I can't find the docs for this bit. Here is an example URI: http://maps.google.com/maps/suggest?q=lon&cp=3&ll=55.0,-3.5&spn=11.9,1.2&hl=en&gl=uk&v=2 which returns: {suggestion:[{query:"London",... I want to use this in python (2.5). Now in proper JSON there would have been quotations around the keys like so: {"suggestion":[{"query":"London",... and I could have used simplejson or something, but as it is I'm a bit stuck. There are two possible solutions here; either I can get to the API code and find an option to return proper JSON, or I do that in python. Any ideas please.

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  • Declaring and creating an object then adding to collection VS Adding object to collection using new

    - by ZeeMan
    Ok so the title may have been confusing so i have posted 2 code snippets to illustrate what i mean. NOTE: allUsers is just a collection. RegularUser regUser = new RegularUser(userName, password, name, emailAddress); allUsers.Add(regUser); VS allUsers.Add(new RegularUser(userName, password, name, emailAddress)); Which snippet A or B is better and why? What are the advantages or disadvantages? The example i wrote was C# but does the language (C#, Java etc) make a difference?

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  • save object associate to another object automatically

    - by Luca Romagnoli
    Hi i have these classes: class Core < ActiveRecord::Base belongs_to :resource, :polymorphic => true belongs_to :image, :class_name => 'Multimedia', :foreign_key => 'image_id' end class Place < ActiveRecord::Base has_one :core, :as => :resource end If i try do launch this: a = Place.find(5) a.name ="a" a.core.image_id = 24 a.save name is saved. image_id no i want save automatically all changes in records in relationship with place class at a.save command. is possible? thanks

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  • expand floating object when floating object within expands

    - by Scarface
    Hey guys, quick question, I have a link when clicked drops down a list. This list is floated to the right to position it properly. This list is in another box that has been floated. My problem is that when the list expands, the box does not and the list comes out of the container box, unless the list is not floated. However floating it seems like the only way to get it to the position I want. If anyone has any ideas on how to solve this problem I would appreciate it. .container-box { margin-top:0px; float:left; padding-left:5px; position:relative; } #box-within { float:right; font-weight:bold; max-height:250px; display: none; background-color:#fff; overflow: auto; width:325px; padding:5px; position:relative; }

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  • Objective-C: alloc of object within init of another object (memory management)

    - by Stefan Klumpp
    In my .h file I have: NSMutableArray *myArray; @property (nonatomic, retain) NSMutableArray *myArray; My .m file looks basically like this: @synthesize myArray; - (id) init { self = [super init]; if (self != nil) { self.myArray = .... ? // here I want to create an empty array } return self; } - (void) dealloc { [self.myArray release]; [super dealloc]; } What I'm not sure about is what do to in the init. 1) self.myArray = [[NSMutableArray alloc] init]; 2) NSMutableArray *tmp = [[NSMutableArray alloc] init]; self.myArray = tmp; [tmp release]; Solution 1 doesn't seem right to me, because of my @property (retain) setting I automatically increase the retain counter when setting self.myArray, but additionally I have already a "+1 retain" due to the [NSMutableArray alloc]. Thus the second solution seems more correct to me, even though it is cumbersome. Also am I wondering if self.myArray = ... is actually the same as [self setMyArray:...] and thus does increase the retain count.

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  • C++ Type error with Object versus Object reference

    - by muddybruin
    I have the following function (which worked in Visual Studio): bool Plane::contains(Vector& point){ return normalVector.dotProduct(point - position) < -doubleResolution; } When I compile it using g++ version 4.1.2 , I get the following error: Plane.cpp: In member function âvirtual bool Plane::contains(Vector&)â: Plane.cpp:36: error: no matching function for call to âVector::dotProduct(Vector)â Vector.h:19: note: candidates are: double Vector::dotProduct(Vector&) So as you can see, the compiler thinks (point-position) is a Vector but it's expecting Vector&. What's the best way to fix this? I verified that this works: Vector temp = point-position; return normalVector.dotProduct(temp) < -doubleResolution; But I was hoping for something a little bit cleaner. I heard a suggestion that adding a copy constructor might help. So I added a copy constructor to Vector (see below), but it didn't help. Vector.h: Vector(const Vector& other); Vector.cpp: Vector::Vector(const Vector& other) :x(other.x), y(other.y), z(other.z), homogenous(other.homogenous) { }

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  • How should an object that uses composition set its composed components?

    - by Casey
    After struggling with various problems and reading up on component-based systems and reading Bob Nystrom's excellent book "Game Programming Patterns" and in particular the chapter on Components I determined that this is a horrible idea: //Class intended to be inherited by all objects. Engine uses Objects exclusively. class Object : public IUpdatable, public IDrawable { public: Object(); Object(const Object& other); Object& operator=(const Object& rhs); virtual ~Object() =0; virtual void SetBody(const RigidBodyDef& body); virtual const RigidBody* GetBody() const; virtual RigidBody* GetBody(); //Inherited from IUpdatable virtual void Update(double deltaTime); //Inherited from IDrawable virtual void Draw(BITMAP* dest); protected: private: }; I'm attempting to refactor it into a more manageable system. Mr. Nystrom uses the constructor to set the individual components; CHANGING these components at run-time is impossible. It's intended to be derived and be used in derivative classes or factory methods where their constructors do not change at run-time. i.e. his Bjorne object is just a call to a factory method with a specific call to the GameObject constructor. Is this a good idea? Should the object have a default constructor and setters to facilitate run-time changes or no default constructor without setters and instead use a factory method? Given: class Object { public: //...See below for constructor implementation concerns. Object(const Object& other); Object& operator=(const Object& rhs); virtual ~Object() =0; //See below for Setter concerns IUpdatable* GetUpdater(); IDrawable* GetRenderer(); protected: IUpdatable* _updater; IDrawable* _renderer; private: }; Should the components be read-only and passed in to the constructor via: class Object { public: //No default constructor. Object(IUpdatable* updater, IDrawable* renderer); //...remainder is same as above... }; or Should a default constructor be provided and then the components can be set at run-time? class Object { public: Object(); //... SetUpdater(IUpdater* updater); SetRenderer(IDrawable* renderer); //...remainder is same as above... }; or both? class Object { public: Object(); Object(IUpdater* updater, IDrawable* renderer); //... SetUpdater(IUpdater* updater); SetRenderer(IDrawable* renderer); //...remainder is same as above... };

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  • How do I handle specific tile/object collisions?

    - by Thomas William Cannady
    What do I do after the bounding box test against a tile to determine whether there is a real collision against the contents of that tile? And if there is, how should I move the object in response to that collision? I have a small object, and test for collisions against the tiles that each corner of it is on. Here's my current code, which I run for each of those (up to) four tiles: // get the bounding box of the object, in world space objectBounds = object->bounds + object->position; if ( (objectBounds.right >= tileBounds.left) && (objectBounds.left <= tileBounds.right) && (objectBounds.top >= tileBounds.bottom) && (objectBounds.bottom <= tileBounds.top)) { // perform specific test to see if it's a left, top , bottom // or right collision. If so, I check to see the nature of it // and where I need to place the object to respond to that collision... // [THIS IS THE PART THAT NEEDS WORK] // if( lastkey==keydown[right] && ((objectBounds.right >= tileBounds.left) && (objectBounds.right <= tileBounds.right) && (objectBounds.bottom >= tileBounds.bottom) && (objectBounds.bottom <= tileBounds.top)) ) { object->position.x = tileBounds.left - objectBounds.width; } // etc.

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  • Unity Problem with colliding instances of same object

    - by Kuba Sienkiewicz
    I want to check if object's instance is overlapping with another instance (any spawned object with another spawned object, not necessary the same object). I'm doing this by detecting collisions between bodies. But I have a problem. Spawned object (instances) are detecting collision with everything but other spawned objects. I've checked collision layers etc. All of spawned objects have rigidbodies and mesh colliders. Also when I attach my script to another body and I touch that body with an instanced object it detects collision. So problem is visible only in collision between spawned objects. And one more information I have script, rigid body and collider attached to child of main object. using UnityEngine; using System.Collections; public class CantPlace : MonoBehaviour { public bool collided = false; // Use this for initialization void Start () { } // Update is called once per frame void Update () { //Debug.Log (collided); } void OnTriggerEnter(Collider collider) { //if (true) { //foreach (Transform child in this.transform) { // if (child.name == "Cylinder") { //collided = true; Color c; c = this.renderer.material.color; c.g = 0f; c.b = 1f; c.r = 0f; this.renderer.material.color = c; Debug.Log (collider.name); //} // } //} //foreach (ContactPoint contact in collision.contacts) { // Debug.DrawRay(contact.point, contact.normal, Color.red,15f); // } } }

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  • SQL SERVER – PAGELATCH_DT, PAGELATCH_EX, PAGELATCH_KP, PAGELATCH_SH, PAGELATCH_UP – Wait Type – Day 12 of 28

    - by pinaldave
    This is another common wait type. However, I still frequently see people getting confused with PAGEIOLATCH_X and PAGELATCH_X wait types. Actually, there is a big difference between the two. PAGEIOLATCH is related to IO issues, while PAGELATCH is not related to IO issues but is oftentimes linked to a buffer issue. Before we delve deeper in this interesting topic, first let us understand what Latch is. Latches are internal SQL Server locks which can be described as very lightweight and short-term synchronization objects. Latches are not primarily to protect pages being read from disk into memory. It’s a synchronization object for any in-memory access to any portion of a log or data file.[Updated based on comment of Paul Randal] The difference between locks and latches is that locks seal all the involved resources throughout the duration of the transactions (and other processes will have no access to the object), whereas latches locks the resources during the time when the data is changed. This way, a latch is able to maintain the integrity of the data between storage engine and data cache. A latch is a short-living lock that is put on resources on buffer cache and in the physical disk when data is moved in either directions. As soon as the data is moved, the latch is released. Now, let us understand the wait stat type  related to latches. From Book On-Line: PAGELATCH_DT Occurs when a task is waiting on a latch for a buffer that is not in an I/O request. The latch request is in Destroy mode. PAGELATCH_EX Occurs when a task is waiting on a latch for a buffer that is not in an I/O request. The latch request is in Exclusive mode. PAGELATCH_KP Occurs when a task is waiting on a latch for a buffer that is not in an I/O request. The latch request is in Keep mode. PAGELATCH_SH Occurs when a task is waiting on a latch for a buffer that is not in an I/O request. The latch request is in Shared mode. PAGELATCH_UP Occurs when a task is waiting on a latch for a buffer that is not in an I/O request. The latch request is in Update mode. PAGELATCH_X Explanation: When there is a contention of access of the in-memory pages, this wait type shows up. It is quite possible that some of the pages in the memory are of very high demand. For the SQL Server to access them and put a latch on the pages, it will have to wait. This wait type is usually created at the same time. Additionally, it is commonly visible when the TempDB has higher contention as well. If there are indexes that are heavily used, contention can be created as well, leading to this wait type. Reducing PAGELATCH_X wait: The following counters are useful to understand the status of the PAGELATCH: Average Latch Wait Time (ms): The wait time for latch requests that have to wait. Latch Waits/sec: This is the number of latch requests that could not be granted immediately. Total Latch Wait Time (ms): This is the total latch wait time for latch requests in the last second. If there is TempDB contention, I suggest that you read the blog post of Robert Davis right away. He has written an excellent blog post regarding how to find out TempDB contention. The same blog post explains the terms in the allocation of GAM, SGAM and PFS. If there was a TempDB contention, Paul Randal explains the optimal settings for the TempDB in his misconceptions series. Trace Flag 1118 can be useful but use it very carefully. I totally understand that this blog post is not as clear as my other blog posts. I suggest if this wait stats is on one of your higher wait type. Do leave a comment or send me an email and I will get back to you with my solution for your situation. May the looking at all other wait stats and types together become effective as this wait type can help suggest proper bottleneck in your system. Read all the post in the Wait Types and Queue series. Note: The information presented here is from my experience and there is no way that I claim it to be accurate. I suggest reading Book OnLine for further clarification. All the discussions of Wait Stats in this blog are generic and vary from system to system. It is recommended that you test this on a development server before implementing it to a production server. Reference: Pinal Dave (http://blog.SQLAuthority.com)   Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology

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  • A simple Dynamic Proxy

    - by Abhijeet Patel
    Frameworks such as EF4 and MOQ do what most developers consider "dark magic". For instance in EF4, when you use a POCO for an entity you can opt-in to get behaviors such as "lazy-loading" and "change tracking" at runtime merely by ensuring that your type has the following characteristics: The class must be public and not sealed. The class must have a public or protected parameter-less constructor. The class must have public or protected properties Adhere to this and your type is magically endowed with these behaviors without any additional programming on your part. Behind the scenes the framework subclasses your type at runtime and creates a "dynamic proxy" which has these additional behaviors and when you navigate properties of your POCO, the framework replaces the POCO type with derived type instances. The MOQ framework does simlar magic. Let's say you have a simple interface:   public interface IFoo      {          int GetNum();      }   We can verify that the GetNum() was invoked on a mock like so:   var mock = new Mock<IFoo>(MockBehavior.Default);   mock.Setup(f => f.GetNum());   var num = mock.Object.GetNum();   mock.Verify(f => f.GetNum());   Beind the scenes the MOQ framework is generating a dynamic proxy by implementing IFoo at runtime. the call to moq.Object returns the dynamic proxy on which we then call "GetNum" and then verify that this method was invoked. No dark magic at all, just clever programming is what's going on here, just not visible and hence appears magical! Let's create a simple dynamic proxy generator which accepts an interface type and dynamically creates a proxy implementing the interface type specified at runtime.     public static class DynamicProxyGenerator   {       public static T GetInstanceFor<T>()       {           Type typeOfT = typeof(T);           var methodInfos = typeOfT.GetMethods();           AssemblyName assName = new AssemblyName("testAssembly");           var assBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assName, AssemblyBuilderAccess.RunAndSave);           var moduleBuilder = assBuilder.DefineDynamicModule("testModule", "test.dll");           var typeBuilder = moduleBuilder.DefineType(typeOfT.Name + "Proxy", TypeAttributes.Public);              typeBuilder.AddInterfaceImplementation(typeOfT);           var ctorBuilder = typeBuilder.DefineConstructor(                     MethodAttributes.Public,                     CallingConventions.Standard,                     new Type[] { });           var ilGenerator = ctorBuilder.GetILGenerator();           ilGenerator.EmitWriteLine("Creating Proxy instance");           ilGenerator.Emit(OpCodes.Ret);           foreach (var methodInfo in methodInfos)           {               var methodBuilder = typeBuilder.DefineMethod(                   methodInfo.Name,                   MethodAttributes.Public | MethodAttributes.Virtual,                   methodInfo.ReturnType,                   methodInfo.GetParameters().Select(p => p.GetType()).ToArray()                   );               var methodILGen = methodBuilder.GetILGenerator();               methodILGen.EmitWriteLine("I'm a proxy");               if (methodInfo.ReturnType == typeof(void))               {                   methodILGen.Emit(OpCodes.Ret);               }               else               {                   if (methodInfo.ReturnType.IsValueType || methodInfo.ReturnType.IsEnum)                   {                       MethodInfo getMethod = typeof(Activator).GetMethod(/span>"CreateInstance",new Type[]{typeof((Type)});                                               LocalBuilder lb = methodILGen.DeclareLocal(methodInfo.ReturnType);                       methodILGen.Emit(OpCodes.Ldtoken, lb.LocalType);                       methodILGen.Emit(OpCodes.Call, typeofype).GetMethod("GetTypeFromHandle"));  ));                       methodILGen.Emit(OpCodes.Callvirt, getMethod);                       methodILGen.Emit(OpCodes.Unbox_Any, lb.LocalType);                                                              }                 else                   {                       methodILGen.Emit(OpCodes.Ldnull);                   }                   methodILGen.Emit(OpCodes.Ret);               }               typeBuilder.DefineMethodOverride(methodBuilder, methodInfo);           }                     Type constructedType = typeBuilder.CreateType();           var instance = Activator.CreateInstance(constructedType);           return (T)instance;       }   }   Dynamic proxies are created by calling into the following main types: AssemblyBuilder, TypeBuilder, Modulebuilder and ILGenerator. These types enable dynamically creating an assembly and emitting .NET modules and types in that assembly, all using IL instructions. Let's break down the code above a bit and examine it piece by piece                Type typeOfT = typeof(T);              var methodInfos = typeOfT.GetMethods();              AssemblyName assName = new AssemblyName("testAssembly");              var assBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assName, AssemblyBuilderAccess.RunAndSave);              var moduleBuilder = assBuilder.DefineDynamicModule("testModule", "test.dll");              var typeBuilder = moduleBuilder.DefineType(typeOfT.Name + "Proxy", TypeAttributes.Public);   We are instructing the runtime to create an assembly caled "test.dll"and in this assembly we then emit a new module called "testModule". We then emit a new type definition of name "typeName"Proxy into this new module. This is the definition for the "dynamic proxy" for type T                 typeBuilder.AddInterfaceImplementation(typeOfT);               var ctorBuilder = typeBuilder.DefineConstructor(                         MethodAttributes.Public,                         CallingConventions.Standard,                         new Type[] { });               var ilGenerator = ctorBuilder.GetILGenerator();               ilGenerator.EmitWriteLine("Creating Proxy instance");               ilGenerator.Emit(OpCodes.Ret);   The newly created type implements type T and defines a default parameterless constructor in which we emit a call to Console.WriteLine. This call is not necessary but we do this so that we can see first hand that when the proxy is constructed, when our default constructor is invoked.   var methodBuilder = typeBuilder.DefineMethod(                      methodInfo.Name,                      MethodAttributes.Public | MethodAttributes.Virtual,                      methodInfo.ReturnType,                      methodInfo.GetParameters().Select(p => p.GetType()).ToArray()                      );   We then iterate over each method declared on type T and add a method definition of the same name into our "dynamic proxy" definition     if (methodInfo.ReturnType == typeof(void))   {       methodILGen.Emit(OpCodes.Ret);   }   If the return type specified in the method declaration of T is void we simply return.     if (methodInfo.ReturnType.IsValueType || methodInfo.ReturnType.IsEnum)   {                               MethodInfo getMethod = typeof(Activator).GetMethod("CreateInstance",                                                         new Type[]{typeof(Type)});                               LocalBuilder lb = methodILGen.DeclareLocal(methodInfo.ReturnType);                                                     methodILGen.Emit(OpCodes.Ldtoken, lb.LocalType);       methodILGen.Emit(OpCodes.Call, typeof(Type).GetMethod("GetTypeFromHandle"));       methodILGen.Emit(OpCodes.Callvirt, getMethod);       methodILGen.Emit(OpCodes.Unbox_Any, lb.LocalType);   }   If the return type in the method declaration of T is either a value type or an enum, then we need to create an instance of the value type and return that instance the caller. In order to accomplish that we need to do the following: 1) Get a handle to the Activator.CreateInstance method 2) Declare a local variable which represents the Type of the return type(i.e the type object of the return type) specified on the method declaration of T(obtained from the MethodInfo) and push this Type object onto the evaluation stack. In reality a RuntimeTypeHandle is what is pushed onto the stack. 3) Invoke the "GetTypeFromHandle" method(a static method in the Type class) passing in the RuntimeTypeHandle pushed onto the stack previously as an argument, the result of this invocation is a Type object (representing the method's return type) which is pushed onto the top of the evaluation stack. 4) Invoke Activator.CreateInstance passing in the Type object from step 3, the result of this invocation is an instance of the value type boxed as a reference type and pushed onto the top of the evaluation stack. 5) Unbox the result and place it into the local variable of the return type defined in step 2   methodILGen.Emit(OpCodes.Ldnull);   If the return type is a reference type then we just load a null onto the evaluation stack   methodILGen.Emit(OpCodes.Ret);   Emit a a return statement to return whatever is on top of the evaluation stack(null or an instance of a value type) back to the caller     Type constructedType = typeBuilder.CreateType();   var instance = Activator.CreateInstance(constructedType);   return (T)instance;   Now that we have a definition of the "dynamic proxy" implementing all the methods declared on T, we can now create an instance of the proxy type and return that out typed as T. The caller can now invoke the generator and request a dynamic proxy for any type T. In our example when the client invokes GetNum() we get back "0". Lets add a new method on the interface called DayOfWeek GetDay()   public interface IFoo      {          int GetNum();          DayOfWeek GetDay();      }   When GetDay() is invoked, the "dynamic proxy" returns "Sunday" since that is the default value for the DayOfWeek enum This is a very trivial example of dynammic proxies, frameworks like MOQ have a way more sophisticated implementation of this paradigm where in you can instruct the framework to create proxies which return specified values for a method implementation.

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