Re: Move From Redhat 7.3 to redhat ES 3.0

[Donn Cave <donn@u.washington.edu>]

On Tuesday, May 11, 2004, at 03:27 AM, Buchan Milne wrote:
...
> The scenario I am working with involves about 8-12 concurrent clients 
> max,
> each doing a single search per bind, and I'm getting about 200/minute 
> (for
> a qmail email address lookup). With multiple searches per bind (not
> relevant to the production load though) we easily get up to 
> >1000/minute.
> Except that RHEL3 is still 5-10* slower.

Yes, one query per connection slows us down quite a bit too.  Depending
on authentication method (SSL vs. GSSAPI-Kerberos), that runs from
60 to 140 per second.  I'm not able to compare RHEL2.1, really, as we
went straight from Redhat 7.3 to RHE3 ("Taroon Update 1".)  The hardware
we configured for LDAP runs about the same under either of those two
releases.

> The boxes I have been benchmarking are P3 Xeon's (thus no HT), which 
> could
> have an impact w.r.t. NPTL.

I don't think 7.3 supports Intel Hyperthread, and it doesn't seem to 
make
a great deal of difference.  In the one case where we had a performance
problem, it looked to me like almost certainly there was a problem with
disk I/O - either in the hardware (HP hardware raid, the disk itself,
who knows) or something about the whole configuration that made disk 
access
inefficient.  I regret leaving local4 syslog configured to a local disk 
log,
since we usually route it off the host and this could add a disk write 
per
access (wouldn't be surprised if syslog fsyncs.)

	Donn Cave, donn@u.washington.edu