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RE: FW: OpenLDAP as an enterprise level LDAP provider (try II)

Quanah, I am going to play with this over the weekend using your
suggestions.  Thanks for the feedback!!


John Fortin
PBG Middleware and Web Services
(914) 767-7844

>-----Original Message-----
>From: Quanah Gibson-Mount [mailto:quanah@stanford.edu] 
>Sent: Wednesday, November 24, 2004 4:23 PM
>To: Fortin, John {PBG}; OpenLDAP-software@OpenLDAP.org
>Subject: RE: FW: OpenLDAP as an enterprise level LDAP provider (try II)
>--On Wednesday, November 24, 2004 3:11 PM -0600 "Fortin, John {PBG}" 
><John.Fortin@pepsi.com> wrote:
>> Quanah, here you go, in order:
>> 	1) Doing the initial slapdd with indexing on never completed  We
>> ended up turning off indexing just to load the initial ldif 
>file.  We then
>> ran slapindex after enabling the indexes.
>This indicates that you have not configured a large enough BDB 
>DB cache 
>size for your database.
>> 	2) Dell 2650, dual 2.1 GHz Intel Zeon processors with 
>> support, 2 Gig Ram, 76 Gig HD with Raid 5.
>You likely need more RAM.
>> 	3) As I indicated, hot backups are not possible due to the
>> slapadd/slapindex issues.  If I can make this perform better 
>then I can do
>> it.
>>       4)DB_CONFIG during load:	
>> 		set_cachesize   0      52428800        0
>> 		set_lg_regionmax        1048576
>> 		set_lg_max              10485760
>> 		set_lg_bsize            1097152
>> 		set_lg_dir              /var/ldapdb/slave2/logs
>> 		set_tmp_dir             /tmp
>> 		set_flags DB_LOG_AUTOREMOVE
>Your DB Cache Size (500MB) is probably too small.
>> I'm tryin to make this work.  I'm surprised at the results 
>too.  If I'm
>> not tuning this properly, I can adjust.  These were values 
>suggested in
>> one of the links in the FAQ, though I did increase set_cachesize.
>> I do vaguely remember someone complaining about performance 
>on RedHat,
>> but I cannot find the reference in the archives.
>Here is what I do to tune the DB size when adding a large DB:
>1) Set it to something rather large (like 1.5 GB), and perform 
>a slapadd 
>with indexing, and see how long that takes.  If it takes a 
>very very long 
>time, it is still going to need more space.  Note that the 
>more indices you 
>have, the larger the cachesize you will need.
>2) You don't seem to have the BDB flags used for doing a fast 
>slapadd in 
>your DB_CONFIG file.  You should add:
># Just use these settings when doing slapadd...
>#set_flags DB_TXN_NOSYNC
>#set_flags DB_TXN_NOT_DURABLE
>to your DB_CONFIG, and unset the last two when doing a 
>slapadd.  That will 
>speed up slapadd's enormously, while still performing 
>indexing.  Once the 
>slapadd is completed, simply comment them out again.
>3) Once you know how long it takes with a large DB Cache, drop 
>some off of 
>it, and slapadd again.  I would guestimate that if it takes 
>more than 30 
>minutes with the above settings & a large cache size on your box, you 
>likely need more DB cachesize.
>Quanah Gibson-Mount
>Principal Software Developer
>ITSS/Shared Services
>Stanford University
>GnuPG Public Key: http://www.stanford.edu/~quanah/pgp.html