I am mounting my /tmp as tmpfs to migrate 'some' disk IO to RAM. I
removed $HOME/.cache directory and create a symbolic link with that name
to a directory in /tmp, like /tmp/some-path/.cache, thus moved all
Tracker cache to /tmp. I did that with $HOME/.local too.
Interesting, is that JUST for Tracker or all caches for all apps?
Because it might just be easier to update the XDG locations so all apps respond to that change - instead of manually creating these links.
What I am wondering is, at start up, what does Tracker do to
$HOME/.cache/tracker and $HOME/.local/share/tracker. How much data does
it do IO on disk read/write?
Yes, on start up there is a bunch of IO, but mainly to check the database opens, the schema is up to date and if there are any updates to perform (both to the schema AND to the data-set). If you successfully indexed and completed it all since last boot, the IO should be fairly small. If you need to finish indexing, it will be moderate to excessive depending on your settings.
And in the case of me that I move those dirs to /tmp, it means at every
startup, Tracker has to do disk read ( any disk write? ) more data than
Yes there is potentially there is IO to write - it really depends on the state of the database compared to the data set you're indexing. If the two are in sync, not much happens other than a few reads.
it does in normal case, right? From what I observed, it's around
200-300MB of data in /tmp/some-path/.cache/tracker.
Well, the databases are stored there. The size depends on the data set and indexing options.