Simpler Navigation for Servers and Operating Systems - Please Update Your Bookmarks
Completed: a much simpler Servers and Operating Systems section of the Community. We combined many of the older boards, so you won't have to click through so many levels to get at the information you need. Check the consolidated boards here as many sub-forums are now single boards.
If you have bookmarked forums or discussion boards in Servers and Operating Systems, we suggest you check and update them as needed.
General
cancel
Showing results for 
Search instead for 
Did you mean: 

CentOs-3.1 (RH ES 3.0) SHMMAX and Sybase Woes

Bryan Dees
Occasional Contributor

CentOs-3.1 (RH ES 3.0) SHMMAX and Sybase Woes

We are currently testing CentOS-3.1 (Redhat ES 3.0) with Sybase 11.0.33 which we use in production over Redhat 7.3. But have run into a problem where the dataserver wont load if we set kernel.shmmax and Sybase 'total memory' above 128mb.

The following is our configuration set at 256mb of shared memory (
sysctl -w kernel.shmmax=`echo 256*1024*1024 |bc` ) = 268435456

SYBASE.cfg <- total memory = 131072
(268435456/2048 = 131072)

free:
Mem: 772080 173836 598244 0 34296 57404
-/+ buffers/cache: 82136 689944
Swap: 1052248 0 1052248
----

ipcs -lm
------ Shared Memory Limits --------
max number of segments = 128
max seg size (kbytes) = 262144
max total shared memory (kbytes) = 8388608
min seg size (bytes) = 1

---
Kernel: 2.4.21-15.0.4.EL
glibc: glibc-2.3.2-95.20
---

The following is output from an strace where we feel is the root of the problem, when attempting to load the dataserver using:
strace -f ./startserver -f ./RUN_SYBASE

--- start paste ---
[pid 2749] shmget(1510068867, 0, 0) = -1 ENOENT (No such file or directory)
[pid 2749] close(4) = 0
[pid 2749] getpid() = 2749
[pid 2749] write(5, "0x5a01d283\n2749\n", 16) = 16
[pid 2749] close(5) = 0
[pid 2749] open("/proc/self/maps", O_RDONLY) = 4
[pid 2749] fstat64(4, {st_mode=S_IFREG|0440, st_size=0, ...}) = 0
[pid 2749] mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb748b000
[pid 2749] read(4, "08048000-0837b000 r-xp 00000000 "..., 4096) = 910
[pid 2749] read(4, "", 4096) = 0
[pid 2749] close(4) = 0
[pid 2749] munmap(0xb748b000, 4096) = 0
[pid 2749] shmget(1510068867, 265158656, IPC_CREAT|IPC_EXCL|0600) = 32768
[pid 2749] shmat(32768, 0xb8000000, 0) = -1 EINVAL (Invalid argument)
[pid 2749] gettimeofday({1094148717, 923538}, NULL) = 0
[pid 2749] write(1, "00:2004/09/02 11:11:57.92 kernel"..., 8300:2004/09/02 11:11:57.92 kernel os_create_region: shmat(32768): Invalid argument
) = 83
[pid 2749] write(3, "00:2004/09/02 11:11:57.92 kernel"..., 83) = 83
[pid 2749] gettimeofday({1094148717, 924334}, NULL) = 0
[pid 2749] write(1, "00:2004/09/02 11:11:57.92 kernel"..., 7500:2004/09/02 11:11:57.92 kernel kbcreate: couldn't create kernel region.
) = 75
[pid 2749] write(3, "00:2004/09/02 11:11:57.92 kernel"..., 75) = 75
[pid 2749] gettimeofday({1094148717, 925303}, NULL) = 0
[pid 2749] write(1, "00:2004/09/02 11:11:57.92 kernel"..., 7600:2004/09/02 11:11:57.92 kernel kistartup: could not create shared memory
) = 76
[pid 2749] write(3, "00:2004/09/02 11:11:57.92 kernel"..., 76) = 76
[pid 2749] setitimer(ITIMER_REAL, {it_interval={0, 0}, it_value={0, 0}}, NULL) = 0
[pid 2749] rt_sigaction(SIGIO, {SIG_IGN}, NULL, 8) = 0
[pid 2749] exit_group(0)
--- end paste ---

Thanks in advance for any help you can provide.

Bryan Dees
bdees@rim.com