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Re: back-mdb status

Gavin Henry wrote:


The report includes a ModRate job and a SearchRate job; both were run
concurrently. Aside from the fact that the average search rate is
over 85,000
searches/second (on a machine that I previously thought was maxed out
63,000), more interesting is the peak of almost 107,000
searches/second. The
result curve drops, flattens, and then raises again, which shows the
of the writers occupying server threads and making then unavailable
readers, until the writer job finishes.

Wow! What are the test servers specs?

It's ada.openldap.org; you already have an account there and can see for yourself.

It's an HP DL585 G5 with 4 AMD Opteron 8354 quad-core processors. The same machine that produced these results last year:


On this run slapd hit 1300% CPU. Core 0, which was fielding ethernet
interrupts, was at 80% handling soft interrupts. I have no idea
whether we can
generate enough load to hit 90% or more there, seems unlikely.

The write rate is pretty slow, as we already knew. I frankly don't
see it
improving very much, given the single-writer nature of MDB.

  -- Howard Chu
  CTO, Symas Corp.           http://www.symas.com
  Director, Highland Sun     http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP  http://www.openldap.org/project/