postgresql error

Hello!

I'm using postgresql (8.0.15) on Gentoo Linux (2.6.27.29-titan #2 SMP
Sun Aug 16 15:12:53 MSD 2009 x86_64 Intel(R) Xeon(R) CPU E5420 @ 2.50GHz
GenuineIntel GNU/Linux)

some time (meybe every four day) postgresql get error to all clients
what try to connect , a can attach strace to it:

postgres(at)calipso ~ $ pg_ctl status -D /var/lib/postgresql/data/
pg_ctl: postmaster is running (PID: 5742)
/usr/bin/postgres -D /var/lib/postgresql/data --silent-mode=true -N 512
-B 1024
postgres(at)calipso ~ $ logout

calipso ~ # strace -p 5742
Process 5742 attached - interrupt to quit
select(5, [3 4], NULL, NULL, {43, 80000}

) = 1 (in [4], left {24, 984000})
rt_sigprocmask(SIG_SETMASK, ~[ILL TRAP ABRT BUS FPE SEGV CONT SYS RTMIN
RT_1], NULL, 8) = 0
accept(4, {sa_family=AF_FILE, path=@""}, [2]) = 6
getsockname(6, {sa_family=AF_FILE, path="/tmp/.s.PGSQL.5432"...}, [21])
= 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|
SIGCHLD, child_tidptr=0x7f5eb0d8f780) = 28691
close(6) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
select(5, [3 4], NULL, NULL, {60, 0}) = ? ERESTARTNOHAND (To be
restarted)
--- SIGCHLD (Child exited) @ 0 (0) ---
rt_sigprocmask(SIG_SETMASK, ~[ILL TRAP ABRT BUS FPE SEGV CONT SYS RTMIN
RT_1], NULL, 8) = 0
wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], WNOHANG, NULL) =
28691
sendto(5, "\2\0\0\0\30\0\0\0\0\0\0\0\23p\0\0\0\0\0\0\0\0\0\0"..., 24, 0,
NULL, 0) = 24
wait4(-1, 0x7fff58938794, WNOHANG, NULL) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigreturn(0x2) = -1 EINTR (Interrupted system
call)
rt_sigprocmask(SIG_SETMASK, ~[ILL TRAP ABRT BUS FPE SEGV CONT SYS RTMIN
RT_1], NULL, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
select(5, [3 4], NULL, NULL, {60, 0}

calipso ~ # cat /proc/sys/kernel/shmmax
33554432
calipso ~ # cat /proc/sys/kernel/shmall
2097152

what is wrong with server?
Thank You.

--
Vasiliy G Tolstov <v(dot)tolstov(at)selfip(dot)ru>
Selfip.Ru