|Subject||Re: [firebird-support] Re: Bad surprise on performance|
> Also it is good to know some raid settings such as stripe\block size, write cache mode,Vlad Khorsun! You are my man! :-)
> presence of BBU (battery for internal cache).
I hope you like the beer I was bringing in Siegburg, because you are
sure in for more!
I took your advice on re-checking cache parameters, and
especially the BBU and found something interesting when reading the
That b**ch of a Raid controller reported some error yesterday and -
automatically, without so much of asking me first - reset all caching
params to "highest security", which meant: write through, no adaptive
read-ahead, and a cache size of ZERO!!!
I changed that back again and did some tests and now, after only a few
tests, it looks like some operations take as long as on the old
hardware, but most complex operations with random updates/inserts are
running 4 times faster than on the old system, and some 100 times
faster than with the cache not operating correctly.
I thought it's a LSI, but it's a FTS (Fujitsu Technology Solutions)
with 512MB Cache (which sounds pretty much to me) and so far I did not
find any option to turn off that behaviour of the BBU. Will have a
discussion with the vendor... I don't want the BBU to automatically
set these things for me on any probably not even serious exception.
Stripe size is 64K, btw.
will do some more tests but looks like I can finish migration to 2.5