Re: Gateway Crashes

[Dirk Zimoch <dirk.zimoch@psi.ch>]

Steven,

when pthread_create() fails, it is probably a problem with stack space 
rather than heap. Each thread gets its own stack space in 2 of the 4 GB 
address space of a 32bit machine. This results in a limitation in the 
number of threads, i.e. the number of IOCs, the gateway can conenct to.

Solution: reduce the stack size for each thread:
ulimit -s 4096

BTW: You can get the same problem with any CA client which connects to 
many IOCs.

Dirk


Steven Banks wrote:
> We are having severe problems with the EPICS gateway, and I'm hoping 
> that someone can help us resolve them.
>  
> The problem is that the gateway is continually crashing whenever we open 
> up a GUI display with requires connection to multiple IOCs.  These are 
> Libera BPM boxes, and we have 98 of them.  We have a status display 
> which shows the status of 33 of these at once.  As we scroll from one 
> display to the other, the gateway invariably crashes.
>  
> (This is a gateway between our office network and our accelerator 
> network, and is used for monitoring the status of the machine from our 
> desktops.)
>  
> The gateway log provides the following information:
>  
> ***************************************************************
> Jun 26 16:01:02 PV Gateway Version 2.0.0.0 [Jun 14 2006 15:10:22]
> EPICS 3.14.6 PID=8840 ServerPID=8839
> EPICS_CA_ADDR_LIST=BROADCAST-ACC
> EPICS_CA_AUTO_ADDR_LIST=NO
> EPICS_CA_SERVER_PORT=Not specified
> EPICS_CA_MAX_ARRAY_BYTES=Not specified
> EPICS_CAS_INTF_ADDR_LIST=CR01GW01-OFFICE
> EPICS_CAS_SERVER_PORT=Not specified
> EPICS_CAS_IGNORE_ADDR_LIST=Not specified
> Running as user ics on host CR01GW01
> Statistics PV prefix is CR01GW01
> pthread_create  error Cannot allocate memory
>  
> Jun 26 16:36:12 !!! Errlog message received (message is above)
> fatal error: epicsThreadCreate
>  
> Jun 26 16:36:12 !!! Errlog message received (message is above)
> ***************************************************************
>  
> Has anyone else seen the memory problems that we are experiencing?  Is 
> this an indication that we are trying to connect to too many PVs at 
> once?  Will purchasing more memory for the gateway perhaps alleviate the 
> problem.  It currently has 512MB but we are planning to upgrade it to 1 GB.
>  
> Dr. Steven M. Banks – Control Systems Engineer
> Australian Synchrotron Project
> Major Projects Victoria
> 800 Blackburn Road
> CLAYTON VIC 3168
> tel: +613 8540 4103
> fax: +613 8540 4200
>
> mailto:steven.banks@synchrotron.vic.gov.au
> http://www.synchrotron.vic.gov.au <http://www.synchrotron.vic.gov.au/>

--
Dr. Dirk Zimoch
Swiss Light Source
Paul Scherrer Institut
Computing and Controls
phone +41 56 310 5182
fax   +41 56 310 4413