David Logan wrote:
mos wrote:
At 09:27 PM 3/31/2006, you wrote:
I have been offering free database hosting for over 4 years and I've
been doing it on a shoestring. My last MySQL server was a generic
1GHz system with 256MB RAM running Redhat 9. The performance was
surprisingly good because the query loads were not typically high.
One persistent problem was the initial connection times. On that
old system if I had less than approx 10,000 separate databases then
the connection times were "fast", and on the order of 1 second or
so. If I had more than 10,000 databases this dramatically changed
the connection times to well over 15 seconds or more.
I always attributed this connection lag to a problem with the
filesystem and the large number of directories. The old server had
RH9 and ext3 with no htree support which I was told could help with
this problem.
I recently bought a new 2.4 GHz system with 1GB of RAM and installed
Fedora 4 with ext3 and htree support. All new hardware, faster
drives, more RAM and updated software. I thought I was golden!
Well, I have 14,000 databases on this new system and it is as slow
as the old 1GHz system.
The tuning articles I've read, and the sample my-*.cnf files that
ship with the tarball appear to apply to the more typical
installation of a single huge database rather than thousands of
individual dbs. Can anyone offer any suggestions?
Thanks,
Gary Huntress
Gary,
Just a guess, but could the problem be the 14,000 directories
you have to store the 14,000 databases? The problem could be the OS
directory structure. Putting the data into fewer databases will
likely solve the problem or perhaps move half of the directories to
another drive.
Mike
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
Hi Gary,
I think that Mike may have hit the nail on the head. I've a few unix
directories with multiple thousand files and they do become a bit of a
problem to manage speedwise. Perhaps, as Mike has suggested, place
half of them on another drive.
The other option could be to run multiple instances of MySQL, each
having a different port number (this could be based on username or
something similar) eg. A-D port 3306, E-H 3307, etc. and reducing the
number of dbs per instance (server) that way.
Regards
I agree with the diagnosis. I'm unsure how to move 1/2 the databases to
a new drive though. That would be the simplest solution. As I
understand it, MySQL will only use 1 data directory, so the best case
would be symlinks. I'm not sure about this but 15,000 symlinks to
multiple drives may be just as slow as 15,000 directory entries. Were
either of you thinking of another way to split up the directories?
Unfortunately, since I assign one database per user, I can't limit the
number created.
Multiiple servers may be my best option.
Thanks,
Gary
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
