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Re: Performance of MDB and BDB Please suggest?



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/