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Re: Poor performance on Solaris

Brett @Google wrote:
On Fri, Feb 25, 2011 at 10:25 AM, Howard Chu <hyc@symas.com
<mailto:hyc@symas.com>> wrote:

        I will note that if you are going to use slowaris, I highly advise you set
        a memory key rather than using on disk cache for BDB if your DB is any
        over about 4 GB.  Other than that, you'll generally just have to deal with
        the fact it will be significantly slower than Linux.

    Actually, you should always use a shared memory key on Solaris. Using
    mmap'd files is just too slow on that OS.

Incidentlly, What is the uniqueness of a shared memory key, is it unique
amoung all instances on a single server ?

The significance of a shared memory key depends entirely on your operating system. But by its nature, shared memory is global to a machine, so you can assume that all keys must be unique on a particular machine.

I have personally only ever needed a shared memory key on one of a group of
ldap servers.

But i noticed that the bdb logs are not written to disk when shared memory is
configured, is this a good or bad thing ?

The use of shared memory has no bearing on how the BDB library writes its transaction logs.

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