Alex Deucher wrote: > Hello, > > I have noticed a strange performance regression and I'm at a loss as > to what's happening. We have a fairly large database (~16 GB). The > original postgres 7.4 was running on a sun v880 with 4 CPUs and 8 GB > of ram running Solaris on local scsi discs. The new server is a sun > Opteron box with 4 cores, 8 GB of ram running postgres 8.1.4 on Linux > (AMD64) on a 4 Gbps FC SAN volume. When we created the new database > it was created from scratch rather than copying over the old one, > however the table structure is almost identical (UTF8 on the new one > vs. C on the old). The problem is queries are ~10x slower on the new > hardware. I read several places that the SAN might be to blame, but > testing with bonnie and dd indicates that the SAN is actually almost > twice as fast as the scsi discs in the old sun server. I've tried > adjusting just about every option in the postgres config file, but > performance remains the same. Any ideas? Vacuum? Analayze? default_statistics_target? How many shared_buffers? effective_cache_size? work_mem? Sincerely, Joshua D. Drake > > Thanks, > > Alex > > ---------------------------(end of broadcast)--------------------------- > TIP 3: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faq > -- === The PostgreSQL Company: Command Prompt, Inc. === Sales/Support: +1.503.667.4564 || 24x7/Emergency: +1.800.492.2240 Providing the most comprehensive PostgreSQL solutions since 1997 http://www.commandprompt.com/ Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate PostgreSQL Replication: http://www.commandprompt.com/products/
