git-annex/doc/bugs/Too_much_system_load_on_startup.mdwn

### Please describe the problem.
When I log in, if git annex is monitoring a large repo, my desktop is very sluggish getting started. Git-annex causes moderate CPU load, but keeps the disk IO very busy -delaying the opening of desktop applications.

### What steps will reproduce the problem?
On Linux, with git-annex set to autostart and monitoring a folder with more than a few hundred files (I have a pdf library of a few thousand journal articles).

### What version of git-annex are you using? On what operating system?
4.20131002 Ubuntu, from Hess's PPA.

### Please provide any additional information below.

I solved this problem by changing the call to git-annex in /etc/xdg/autostart/git-annex.desktop from:

Exec=/usr/bin/git-annex assistant --autostart

to

Exec=sleep 5 ionice -c 3 /usr/bin/git-annex assistant --autostart

This delays the start of git-annex for 5 seconds, letting the desktop get started, and forces git-annex to yield IO to other programs -preventing it from slowing them down by forcing them to wait for disk access. Since this is a background daemon with potentially high IO usage, but no need for quick responsiveness, perhaps that would make a decent default?

> Added 5 second delay to existing ionice. Provisionally [[done]],
> although it does occur to me that the startup scan could add some delays
> in between actions to run more as a batch job. --[[Joey]]
2013-10-25 15:14:02 +00:00			`### Please describe the problem.`
			`When I log in, if git annex is monitoring a large repo, my desktop is very sluggish getting started. Git-annex causes moderate CPU load, but keeps the disk IO very busy -delaying the opening of desktop applications.`

			`### What steps will reproduce the problem?`
			`On Linux, with git-annex set to autostart and monitoring a folder with more than a few hundred files (I have a pdf library of a few thousand journal articles).`

			`### What version of git-annex are you using? On what operating system?`
			`4.20131002 Ubuntu, from Hess's PPA.`

			`### Please provide any additional information below.`

			`I solved this problem by changing the call to git-annex in /etc/xdg/autostart/git-annex.desktop from:`

			`Exec=/usr/bin/git-annex assistant --autostart`

			`to`

			`Exec=sleep 5 ionice -c 3 /usr/bin/git-annex assistant --autostart`

			`This delays the start of git-annex for 5 seconds, letting the desktop get started, and forces git-annex to yield IO to other programs -preventing it from slowing them down by forcing them to wait for disk access. Since this is a background daemon with potentially high IO usage, but no need for quick responsiveness, perhaps that would make a decent default?`
assistant: When autostarted, wait 5 seconds before running the startup scan, to avoid contending with the user's desktop login process. 2013-10-26 16:42:58 +00:00
			`> Added 5 second delay to existing ionice. Provisionally [[done]],`
			`> although it does occur to me that the startup scan could add some delays`
			`> in between actions to run more as a batch job. --[[Joey]]`