Thanks Dimitry for clarifications.

I did not know about $this syntax. This is indeed explained here.

This will call the child/extended method and the superclass method, I want to bypass that and call base/super method directly.

Can you provide a link to the documentation (or an example) that show how to use the classes you mention in Ensemble ? 

EDIT : is this what you are talking about when referencing "pool sizes" : 
https://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=ECONFIG_PoolSize

I have enabled the logs and here is what I got (several times) : 

Initialization
Apache Worker Process Initialization: PID=11330; Configuration=0x7fe92f816000;

Establish a new connection
Connection-No=156:0; Gateway PID=11330; 
      InterSystems IRIS Server=IRIS (xxx.xxx.xxx.xxx:56773);
      InterSystems IRIS PID=31932
      
(...)

Close Down
Apache Worker Process Close Down: PID=11330; Configuration=0x7fe92f816000;

This is on the non working server. The other one does not have such events, unless Apache is restarted (since there is no need to recreate new connections every time).

mpm module: MaxConnectionsPerChild (also named MaxRequestsPerChild in older versions) is set to 0. According to Apache docs, this means the process should never expire (but it does as seen in the logs). This is also the recommended setting from the InterSystems page you mentioned. MaxSpareThreads is not set on both servers (unlike what is recommended by InterSystems).

Intersystems page also recommend to use a "NSD based Gateway configuration" if needed. That's not what I use. Both servers load the /opt/webgateway/bin/CSPa24.so module, not the mod_csp24.so one.

Also: I have notified a difference in Apache version. The non working server use an older one. I will try upgrading it.

I have checked the specific web application that I used during testing and they are exactly the same on both side. I don't think it's related to licensing or sessions. The behavior described in the OP occurs even for requests that does not require a license or session.

Thanks for you help. I took a look at Apache and I couldn't find anything wrong with it. Here is a summary of it :

LoadModule csp_module_sa /opt/webgateway/bin/CSPa24.so
CSPFileTypes csp cls zen cxw
CSPModulePath /opt/webgateway/bin/
CSPConfigPath "/opt/webgateway/bin/"

<Location "/csp/bin/Systems/">
    SetHandler cspsys-handler-sa
</Location><Location "/csp/bin/RunTime/">
    SetHandler csp-handler-sa
</Location>

Alias /iris/csp/ "/opt/webgateway/iris/csp/"
Alias /csp/ "/opt/webgateway/iris/csp/"

<Directory "/opt/webgateway/iris/csp">
    CSPFileTypes csp cls zen cxw
    AllowOverride None
    Options MultiViews FollowSymLinks ExecCGI
    Require all granted
    <FilesMatch ".(log|ini|pid|exe)$">
        Require all denied
    </FilesMatch></Directory><Directory "/opt/webgateway/bin/">
    AllowOverride None
    Options None
    Require all granted
    <FilesMatch ".(log|ini|pid|exe)$">
        Require all denied
    </FilesMatch></Directory><Location "/csp/">
    Require all granted
</Location><Location "/csp/bin/Systems/">
    SetHandler cspsys-handler-sa
    Require ip xxx.xxx.xxx.xxx
</Location><Location "/csp/bin/RunTime/">
    SetHandler csp-handler-sa
    Require ip xxx.xxx.xxx.xxx
</Location><LocationMatch "/csp/(sys|user|samples|docbook|documatic)/">
    Require all denied
</LocationMatch>

For debugging reasons : I wanted to dump the stack to a global, to find out from where some piece of code was called.

Thanks. Do you have any reference to the official documentation for this @something@ syntax ?

EDIT : found it. It's called Subscript Indirection.

I have tried that that command but all I got in message.log is this : 

[Generic.Event] $ZF(-100) cmd=netstat -ano -p tcp
[Generic.Event] $ZF(-100) ret=0

Is there something special to enable (like some flags that prevent full dump) ?
The documentation does not say much about it.

Hi. AFAIK this only show the current active output device (eg: the last one set by USE command). There can be many underlaying connections under that process.

Thanks a lot. I will try that ASAP.

You are probably talking about this : 

https://docs.intersystems.com/irislatest/csp/documatic/%25CSP.Documatic…

I didn't know it existed. I will take a look.

EDIT: busted by Chad 

Locks are part of gmheap but you could allocate them in advance locksiz.

So what is specified in locksiz is already "reserved" from gmheap ? (eg: you cannot run out of memory for locks because of excessive gmheap usage).

This is exactly what I was looking for. Thanks a lot Robert.

I did some a check on local machine : KeyLicenseUnits returns 10. So limit is somewhere else. What you say, by the way is true for CSP requests (which is example I give in the OP).

Yes I did. Btw : is there a way, using code, to temporarily elevate current user to perform a specific task ? (eg: to call a function that require %Admin_Secure)

This fixed the issue. Thanks. As Info :

zw%objlasterror

This does not output anything.

Transaction is created during import of data, so unless there is some serious optimization it's difficult to shrink time. Data consistency is important but it's might be OK to accept some tradeoffs. 

Thanks. I will take a look at it. I have some issues on a server where too many "delocks" are created because a lot of persistent objects are created in a long term transaction. I would like to avoid refactoring all the code to bypass persistent objects and use globals directly (which will require a lot of work).

Both are set to "deu8". I checked properties : 

The only difference is in collation tables. Both are set to "German2", but "Additional" column is not the same : 
CACHE : Cache standard, German1, German3
IRIS : German1, German3, German5, IRIS standard
I guess that's the reason. Not sure how it can be fixed (so CACHE behave like IRIS). All "edit" buttons are grayed.

Both servers have region set as "German (Switzerland)". I checked the rest (eg: "Time, Date, Advanced settings", ...) and everything seems 1:1. Is there a specific setting I should check ?

I forgot to mention I am on Windows.

"iris terminal" works somehow. There is several issues with this approach :

- it does not redirect input/output (eg: echo 50 | iris terminal IRIS). One workaround is to put commands into a routine and call it explicitly : iris terminal IRIS MYROUTINE %SYS

- it does not block/wait until completion (which is an issue since I use that command from a deployment tool that need to know once it's done)

- there is no way to provide custom credentials (eg: execute commands with a specific user)

Thanks. This is the same trick as what I found in "InterSystems IRIS Adoption Guide".

If I wrote this in command line (eg: iris session IRIS), it outputs the command line documentation (which indicate something went wrong). "iris console IRIS" works by the way. Do I need to enable something before I can use session parameter ?

EDIT : it seems that irissession.exe is the equivalent on Windows.

Thanks. Out of curiosity, can you show the extended syntax to call a method from another namespace ?

Also : when you say Config.MapGlobals use globals in %SYS, what are they used for ? AFAIK mappings are stored in IRIS.cpf file, not in globals (or maybe you are referring something else).

If you want, i can post a skeleton class where you can start with.

That would be really great.