I have a particular performance problem under a system installed.
In the lab I have an old Microside + Dual Core machine 1GB RAM with 40gb HD IDE and a newer machine HP DL 380 G5 4GB RAM and 500GB SAS under RAID 0 (4 disks) P400i Smart Array Controller.
**Both with Linux Kernel 2 .4.37.9 and Postgresql 7.2**
Under a insertion test we get a performance of 2.5 secs under 2000 inserts (table with a single char(50) column) in the IDE disk. And 500GB RAID 0 (4 disks!) and 37.5 secs under the same test!
I tried: - All the postgresql.conf tuning possibles - All the kernel tuning values possibles - fstab mount options - limits.conf values - I/O tests with boonie++ that shows that P400 is superior than IDE - as expected - 'massive' Google search combinations without answers - Mandriva 2009.1: result is about 12 secs (but it need to be kernel 2.4 with PGSQL 7.2)
The real case: ~100k database insertions that runs in 2 min in the IDE, against ~40 minutes (P400i) in the HP.
The same test in the HP Blade G5 P200 controller works fine.
