Bug 5569 - Feature request: dlopen should cache its modules
Summary: Feature request: dlopen should cache its modules
Alias: None
Product: Samba 4.0
Classification: Unclassified
Component: AD: LDB/DSDB/SAMDB (show other bugs)
Version: unspecified
Hardware: All All
: P3 enhancement (vote)
Target Milestone: ---
Assignee: Andrew Bartlett
QA Contact: samba4-qa@samba.org
Depends on:
Reported: 2008-06-28 04:51 UTC by Volker Lendecke
Modified: 2010-08-30 01:49 UTC (History)
0 users

See Also:


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Description Volker Lendecke 2008-06-28 04:51:55 UTC
To reduce load on the dynamic linker, dlopen should cache the modules it opened. At ldb_connect time only the init function should be called, the module does not have to be fetched from disk again.

According to irc:

11:46           vl > abartlet: question -- why do I get the "trying to load 
                     <module>" whenever I issue a lsaquery call against s4?
11:47           vl > abartlet: Couldn't smbd keep a list of loaded modules and 
                     just call the init function when needed?
11:47     abartlet@> yeah, it currently makes one database connection per 
11:48     abartlet@> 'use' - such as an LSA bind (kept for the whole session)
11:48           vl > abartlet: Sure, that part is ok. I mean it a level lower. 
                     Keep a list of dlopen'ed files.
11:48           vl > This should reduce the load on dlopen considerably.
11:48     abartlet@> but that can seem excessive, and simply loading them off 
                     the disk is what tridge noticed was slowing us down
11:48     abartlet@> yeah, that seems very reasonable
11:48           vl > shall I file a bug report with that?
11:49     abartlet@> please do
Comment 1 Matthias Dieter Wallnöfer 2008-09-12 04:56:09 UTC
Marking as "Feature request"
Comment 2 Matthias Dieter Wallnöfer 2009-10-23 04:08:49 UTC
Update on this report: we've now shared SAMDB contexts and better LDB-TDB indexes on s4 so a huge speedup was achieved. So my question: should we still keep this "dlopen" request open? Does it bring us still more performance?
Comment 3 Volker Lendecke 2010-08-30 01:49:30 UTC