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Re: Performance issues lately.

No real reason, tried various different settings but to no real advantage.

Now I have:

Filesystem             size   used  avail capacity  Mounted on
swap                    19G   7.7G    11G    42%    /tmp

# grep cache DB_CONFIG
set_cachesize 8 0 1

# time /usr/local/BerkeleyDB.4.8/bin/db_stat -d id2entry.bdb
real    6m6.099s

# time cp id2entry.bdb /dev/null
real    0m0.040s
(It's not on disk)

I thought to delete id2entry.bdb, and use slapindex to re-generate it but that appears not to be a supported feature. slapindex can not run without a valid id2entry.bdb. This is why I tried slapcat, rm *, slapadd. But no difference in speed up.

If I truss with -u *:* (All inter-library calls) I get no "single" large system call, just a lot of work somewhere (that does not call read/write etc). Alas, the number of lines in truss file is:
 6209933 /var/tmp/db_stat_truss


Quanah Gibson-Mount wrote:
--On Sunday, November 14, 2010 7:13 PM +0900 Jorgen Lundman
<lundman@lundman.net> wrote:

dbconfig set_cachesize 4 0 8

Why are you breaking your cache into segments? This has always had a
negative performance impact in all tests I've done, and stopped being
necessary to do with BDB 4.3 and later.



Quanah Gibson-Mount
Principal Software Engineer
Zimbra, Inc
Zimbra :: the leader in open source messaging and collaboration

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