Re: index doesn't work?

[Zhang Weiwu <zhangweiwu@realss.com>]

Zhang Weiwu wrote:
> Quanah Gibson-Mount wrote:
>   
>> --On Wednesday, November 07, 2007 10:37 PM +0800 Zhang Weiwu
>> <zhangweiwu@realss.com> wrote:
>>
>>     
>>> My question is: The 4 minute search time is not reasonable (Excel can do
>>> much faster with same number of records), and not acceptable for our use
>>> (because checking modification history is daily routine). How can I
>>> improve it? What other information I didn't provider to have asked this
>>> question properly? What else (besides admin manual which only described
>>> indexing a few pages) should I read?
>>>       
>> Sounds like your index may be corrupt, or you haven't properly tuned
>> the DB_CONFIG file for the accesslog DB.  Alternately, when you ran
>> slapindex, you failed to specify which database to index.  See the -b
>> and -n options to slapindex.
>>     
> Thank you for the hint. As I explained my index is produced with -b
> option. When I try to tweak settings in DB_CONFIG I found tutorials
> about it <http://k12linux.mesd.k12.or.us/ldap/performance.html> which
> suggest me this:
>
>     The size of dbcachesize should be big enough to hold your largest
>     index file (*.dbb).
>
> Unfortunately I do not have any *.dbb file. Besides log files I only get
> several other files that looks like index files (they ends in .bdb)
>
> -rw-rw---- 1 openldap openldap 126M 2007-11-09 10:35 dn2id.bdb
> -rw-rw---- 1 openldap openldap 1,7G 2007-11-09 10:35 id2entry.bdb
> -rw-rw---- 1 openldap openldap 2,1M 2007-11-09 10:35 reqDN.bdb
> -rw-rw---- 1 openldap openldap  13M 2007-06-03 13:28 reqStart.bdb
> -rw-rw---- 1 openldap openldap 660K 2007-11-09 10:35 reqType.bdb
>
> Since the biggest file (id2entry.bdb) is at 1,7G, does that suggest I
> should have dbcachesize of that size? I cannot understand why the cache
> can be so large, after all there are only 50,000 records in it. After
> all the query result of 'ldapsearch reqStart=* reqstart' is only 6.8MB.
> But anyway I added these configuration:
>
> dbcachesize 1740000000
> cachesize 6000
>
> Which is very close to my biggest .bdb file size / number of records.
> The query time is reduced from 4 minutes to 3 minutes, still far from
> user expectation (less than 10 seconds). Tested query is like this:
>
> (reqDN=uid=paul_smith,ou=contacts,ou=xxx,dc=xxx,dc=xxx) 
>
> I am going to try a lot more experiments, but would also like to hear if
> there are something looking significantly wrong in my system? Thank!
>
>   
This time I think I am able to answer my own question.

   1. id2entry.bdb is not only an index, it looks like the whole database;
   2. the tutorial I refer to is about ldbm while I am using bdb.
      (should have noticed this when there is a difference in file
      extension name)

Sorry for your time because of my stupid mistake.