Bug 289431

Summary:	[Akonadi Nepomuk Feeder] 100% CPU usage spikes, KDE 4.8
Product:	[Frameworks and Libraries] Akonadi	Reporter:	Alejandro Nova <alejandronova>
Component:	Nepomuk Feeder Agents	Assignee:	kdepim bugs <kdepim-bugs>
Status:	RESOLVED NOT A BUG
Severity:	normal	CC:	cfeck, sebastian, vkrause
Priority:	NOR
Version:	4.8
Target Milestone:	---
Platform:	Unlisted Binaries
OS:	Linux
Latest Commit:		Version Fixed In:

Description Alejandro Nova 2011-12-20 15:00:28 UTC

Version:           4.8 (using Devel) 
OS:                Linux

This is a complex report, and I will need some help to fully understand it.

1. The akonadi-nepomuk-feeder is indexing mails one by one in KDE 4.8 RC1.
2. The mail indexing process is a terribly inefficient one.
3. All of that results in:
a) lots of CPU being wasted by Virtuoso. This is pure waste (i.e. strace gives me this: futex(0x2abf454, FUTEX_WAIT_PRIVATE, 109, NULL))
b) reindexing after reindexing. The Akonadi Nepomuk feeder simply doesn't know when it has indexed something, so, whenever I reboot or restart my session, it simply starts over.

Reproducible: Always

Steps to Reproduce:
1. Setup 2 separate mail accounts, one with POP3 and the other with IMAP.
2. Enable the Akonadi Nepomuk Feeder agent.
3. Watch it index your mails.

Actual Results:  
- Virtuoso CPU usage stays at 100% for a long passage. It will eventually normalize, after ~18 hours of uptime, with 2 mail folders totalizing 40,000 mails.
- Mail indexing takes an abnormally long time (a full Strigi indexing of my home folder takes a lot less)
- Akonadi Nepomuk feeder can't identify already indexed mail, so, it always starts from scratch.

Expected Results:  
- Virtuoso CPU usage stays normal. It spikes only when actually working.
- Virtuoso can know when something has been indexed and when something hasn't.
- Mail indexing takes less than a full Strigi indexing of my home folder.

Comment 1 Alejandro Nova 2011-12-20 23:49:00 UTC

No, this isn't proper testing. Will wait for an official RC1 release and come back if I'm still getting this.

Comment 2 Alejandro Nova 2011-12-21 02:20:59 UTC

Reverted to a proper KDE 4.8 install, and rereporting.

This bug is about the Akonadi Nepomuk feeder forcing Virtuoso into spikes of 100% CPU usage (where 200% represent two cores, 400% four cores, and so on).

- The bug happens when the Akonadi Nepomuk feeder index mails. There is an option in the UI to disable mail indexing; the Akonadi Nepomuk feeder simply ignores it.
- Reproduction instructions: haven't changed.
- What has changed: I had mixed trunk snapshots with Chakra packages, breaking my install. Now I reverted to a full and clean install, and there are problems.

Comment 3 Alejandro Nova 2011-12-21 02:23:36 UTC

I need to better triage this.