[mythtv-users] Very slow mythfrontend, mysql at 100%
Michael T. Dean
mtdean at thirdcontact.com
Thu Nov 19 19:05:21 UTC 2009
On 11/19/2009 01:46 PM, Ronald Pijnacker wrote:
> My primary frontend is very slow since a while.
> Deleting recordings etc. is taking seconds, which is very annoying.
> I noticed that mysql is at 100% cpu on the backend.
> Could it be that over the years mythconverg has become so big that
> this is the cause of the issue?
>
> If so, which tables can I safely purge?
No, MythTV cleans up the data in the mythconverg database--and besides,
myth doesn't use that much data, so even if stuff wasn't being cleaned
up, it wouldn't get that large.
Something else is going on.
I have a clean mythconverg database and get:
# du -sh /srv/mysql/mythconverg/
448M /srv/mysql/mythconverg/
(that's 448MiB). That's not very big from a MySQL standpoint but is
probably rather large from a mythconverg standpoint. My performance is
fine, though.
I'd guess it's more likely schema corruption (i.e. missing/broken
indices, etc.--and, yes, I saw that you said in IRC it's not crashed
tables, but I mean broken schema) or something.
If you'd like to get Myth to recreate your schema (and all indices,
etc.) see http://www.mythtv.org/wiki/Database_Backup_and_Restore and:
a) Back up your DB
b) Drop your DB
c) Create a new DB with mc.sql
d) Create a new DB schema by running and exiting mythtv-setup
e) Do a partial restore (
http://www.mythtv.org/wiki/Database_Backup_and_Restore#Partial_restore_of_a_backup
)
f) Run mythtv-setup to reconfigure mythbackend
g) Start mythbackend
h) Run mythfrontend and reconfigure mythfrontend and all your plugins
Mike
More information about the mythtv-users
mailing list