[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: Performance of MDB and BDB Please suggest?

Hi ,
Chirs and Howard,
Please share the slapd.conf for MDB for which you have done the performance testing..

On Fri, Aug 24, 2012 at 11:46 PM, Howard Chu <hyc@symas.com> wrote:
Chris Card wrote:
>>>>> I am using openldap 2.4.32 on centos 6, on a 24 core box with 132 Gb RAM.
>>>>> My test directory has ~ 3 million entries, and I loaded it into mdb using
>>>> slapadd which took over 2 days (by comparison, the same load into bdb takes
>>>> 2-3 hours).
>>>> This is not normal. With slapadd -q MDB is faster than BDB assuming you're
>>>> using a decent filesystem and sensible mount options. JFS, EXT2, do better
>>>> than other filesystems in my tests. Very recent EXT4 may be better than EXT3
>>>> as well.
>>> The filesystem is xfs, mounted as a drbd device (although at the moment the other
>>> half of the drbd pair is not configured, so it doesn't have to wait for synchronous
>>> writes across the network)
>> Sounds like you're not using slapadd -q. Either that, or your filesystem cache
> Oh ****! You're quite right, I managed to lose the -q from the slapadd command when copy/pasting
> from a script. I'll try running it again with -q.
> Do you have an ETA for improvements to mdb write performance?

Not at this point. There are several approaches to test; most of them will
probably be dead ends.

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