Re: Shared Memory Not released

>Brian Li <cphdcbl@ted.cs.depaul.edu> wrote in article ><511nel$aft@shrike.depaul.edu>... >> >> Dear Informix experts, >> >> We are currently have Informix Dynamic Online running on our HP T500 >machine >> and recently have shared memory problem which is only known to be solved Unix Kernel Parameters you will have to check: SHMMAX - Maximum size of a shared memory segment SHMSEG - Maximun size of shared memory segments per process SHMMNI - Maximun number of segments for your UNIX system SHMMAX * SHMSEG how much shared memory Online could access SHMMAX * SHMMNI how much shared memory in your Unix system There are many factors influencing memory usage, try to check and adjust buffer pool with BUFFERS, Limit the amount of memory DSS queries can use with DS_TOTAL_MEMORY, Constrain the total amount of shared memory used with SHMTOTAL ( in your case SHMTOTAL is set too low, operations that require more memory than what is available may fail. As a rule you probably want to set SHMTOTAL well above the normal amount of shared memory used by DSA. You must set the SHMVIRTSIZE (Limited by SHMMAX in unix ) parameter to a size that can fit your normal daily operations,if you are tuning your ENGINE try to set SHMTOTAL to 0 until you calculate the number of total shared memory your OnLine System will require. It is not good for DSA to add virtual segments to shared memory constantly (remember that there is a UNIX KERNEL that limits this situation) and INFORMIX doesn't recommend it. For better performance, remember to attach shared memory to the physical memory, setting forced residency to 1. You can determine the total Shared Memory Usage by executing onstal -g seg from your command line, it will display about how much memory is allocated and used by INFORMIX-OnLine Dynamic Server. You can free unused shared memory segments ( onmode -F ) , the memory grant manager MGM examines every pool and frees any unused memory, and examines every segment and frees any unused segments. You may experience some degradation in performance during command execution. I would be pleased to help you configure more efficient your OnLine System if you post a mail indicating your hardware, users (Physical Users) , How do they connect (tcpip, attached to shared memory ), a copy of your TBCONFIG file. I know a tuning must be done directly but it would be good any way to take a look at your configuration. I Love Informix DSA. I hope this can help you, Regards, ------------------------------------------------------------------ Mario Estrada Rosa ( LESCO, S.A. ) Guatemala City, Central America lesco@guate.net Phone (502) 3-318116 Fax (502) 3348447 ------------------------------------------------------------------ -------------------------------------------- Mario Estrada Rosa (LESCO,S.A.) Systems Enginner lesco@guate.net Phone (502) 3318116 Fax (502) 3348447 --------------------------------------------