17 Jul
2008
17 Jul
'08
12:25 p.m.
On Thursday 17 July 2008, Sajith T S wrote:
How is the overall experience like re. deploying
openser with mysql
clusters? Are there gotchas etc that need to be taken care of? (For
example, a 2006 article [1] says that "The MySQL NDB engine currently
runs its database completely in memory. This means that you have to be
able to fit your database in memory." But this is not documented as a
limitation in mysql faq.) Non clustered experiments were occasionally
catastrophic, so can't risk taking that route again.
Somebody suggested using drbd [2], but I did not quite like it -- it
needs kernel modules, has more administrative overhead, is tied to
linux, it is not clear how consistency (ie, state of in-memory data
and on-disk data) is taken care of, and in any case ndbcluster appears
to be the clustering solution with official stamp of approval.
(Related - is postgres any better? Apparently postgres' clustering
capabilities are "better", but then cdrtool etc seems to be written
with mysql as the primary target.)
Hi Sajith,
recent MySQL cluster versions don't have this limitation (for non-index
columns AFAIK) any more, you can store this data on the disk. There are some
people that run openser with mysql cluster on this list, it was also
discussed a few times in the past here.
I can't comment on drdb and on postgres clustering, but in openser is mysql
the main target too. I did recently some work in this area, trying to even
the differences between the database connectors. But mysql is IMHO still the
most stable option, as it gets the most testing from the users.
Cheers,
Henning