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Re: slapadd/bdb tuning newbie
Gary LaVoy wrote:
Ok, I admit it, when I go through the BDB docs, they are pretty daunting
to me regarding how to effectively "tune" openldap for various things.
I imported about 750,000 records in to the db using slapadd. It took
over *52 hours* - so I am not tuning something right, but I am really
not sure what I set wrong or maybe didn't include.
I'm surprised you waited so long to let it finish. I suppose it's a good
excuse to get other work done though...
I am running openldap 2.1.22 and BDB 4.1.(latest) as this is what ships
currently on OS X 10.3 stock. Xserve 1.0 Gh Dual CPU with 2 Gb RAM.
That's too bad. There's easily 80 or so bug fixes between 2.1.22 and the
current (2.1.30) release, countless fixes between 2.1.X and 2.2. Perhaps
your vendor needs help staying up to date. (Oh, wait, you *are* the
Here is the slapd.conf entry for that DB that I set up (I have 3
separate DB in the file) (yes I need all those indexes)
and here is the DB_CONFIG I used:
(I picked these based on a first attempt to get it to be faster than
with no config since everything I have ever read says you better have one.)
# Set the database in memory cache size.
set_cachesize 0 52428800 0
Now that you've invested those 52 hours in loading this thing, did you
look at db_stat to see how well this cache performed? Have you looked at
the stats on the individual database files to see how many pages they
each consume? It seems, given your 2GB RAM available, that the 52MB
you've configured here is rather miserly. But without knowing the
overall data volume you're dealing with, it's impossible to draw any
# Set log values.
Have you actually mounted a separate disk under this directory path? As
the docs state in several places, you need to put the logs on a
physically separate spindle from the database files to get the best
performance. Otherwise, just realize that however large your input data
is, your single disk needs to handle double-to-triple that data volume
because all of the data and all of the logs are going on the same disk,
and there's a ton of seek overhead along with it all. Not even RAIDs
perform well in the face of heavy random access patterns...
The BDB library doesn't use temporary files in back-bdb, so this setting
-- Howard Chu
Chief Architect, Symas Corp. Director, Highland Sun
Symas: Premier OpenSource Development and Support