I don't think there would be any benefit to using InnoDB, at least not
from a transaction support view.
After your nightly optimize/repair are you also doing a flush? That may
help.
I haven't seen any direct comparisons between HFS+ and file systems
supported by Linux. I would believe that Linux would be faster since
Linux tends to be geared towards performance first rather than
usability. But you shouldn't rely on disk caching only. The disks still
need to be read in order to fill the cache, so you want to get the best
disk performance you can. Based on your other email, it looks like you
are using individual disks for storing your data. While I understand
what you were trying to do by separating your data onto different
disks, you would get far better performance by combining your disks in
a RAID, even a software RAID.
If you are using software based RAID, you would need to choose between
mirroring or striping. Both will give you better read speeds, mirroring
will slow down writes. If you are striping, the more drives you use the
better performance you'll get, although I wouldn't put more than 4
drives on a single SCSI card.
I think you can use Apple's RAID software for your SCSI disk, but
SoftRAID (softraid.com) would give you more options. Moving to RAID
should improve things across the board and will give the best bang for
your buck (SoftRAID is $129). Personally, I think you should always use
some form of RAID on all servers.
On Jan 26, 2004, at 5:41 PM, Adam Goldstein wrote:
> I have added these settings to my newer my.cnf, including replacing
> the key_buffer=1600M with this 768M... It was a touch late today to
> see if it has a big effect during the heavy load period (~3am to 4pm
> EST, site has mostly european users)
>
> I did not have any of these settings explicitly set in my latest
> my.cnf trialsm, except key_buffer, and I ommitted the innodb ones, as
> we are not (currently) using innodb... would there be any benefit?
> transactions are not a priority, so says my client, so he does not use
> them.
>
> I see the query_cache_size is rather large here, but I am unsure what
> the default size would be. I do not know, yet, how large I can/should
> make either setting, but, it does appear to work without malloc/memory
> errors appearing in the log. Note: while it bitched in the logs about
> the malloc setting, the server did not crash, but, kept running.
> Obviously with an undetermined amount of cache. I cannot seem to find
> any good way to know how much ram (cache/buffer/other) mysql uses, as
> the top output from osx is not very appealing... not that linux top
> tells me much more either. On average, on the old system (all on one
> box) mysql was said to be using about 350MB avg in top... except after
> the nightly optimize/repair script which left it using 1.2G of ram for
> hours, and making all queries rather slow.
>
> Also- a more G5 specific question: as MySql is supposed to gain much
> from the OS disk caching, how does OSX/HFS+ compare to other *nIX
> filesystems... such as Linux 2.4 w/reiserfs?
>
--
Brent Baisley
Systems Architect
Landover Associates, Inc.
Search & Advisory Services for Advanced Technology Environments
p: 212.759.6400/800.759.0577
