On Oct 13, 2006, at 17:13 , Andrew - Supernews wrote:
On 2006-10-13, Alexander Staubo <alex@xxxxxxxxxxxxxxx> wrote:
On my box (Dell PowerEdge 1850, dual Xeon 2.8GHz, 4GB RAM, 10kRPM
SCSI, Linux 2.6.15, Ubuntu) I get 1,100 updates/sec, compared to
10,000 updates/sec with MySQL/InnoDB, using a stock installation of
both. Insert performance is only around 10% worse than MySQL at
around 9,000 rows/sec. Curiously enough, changing shared_buffers,
wal_buffers, effective_cache_size and even fsync seems to have no
effect on update performance, while fsync has a decent effect on
insert performance.
Your disk probably has write caching enabled. A 10krpm disk should be
limiting you to under 170 transactions/sec with a single connection
and fsync enabled.
What formula did you use to get to that number? Is there a generic
way on Linux to turn off (controller-based?) write caching?
Alexander.
