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From:Bruce Dembecki Date:February 11 2005 8:37pm
Subject:<no subject>
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"Hannes Rohde" <hr@stripped> wrote:
> innodb_data_file_path=ibdata1:2G:autoextend
> innodb_buffer_pool_size=1200M
> innodb_additional_mem_pool_size=20M
May not solve the replication issue, but if this is a 4GByte server that is
dedicated to MySQL (ie you aren't using memory for anything else, like..
say... a web server or something) and the MySQL server is dedicated to
InnoDB which the other memory settings seem to support - then you need to
revise this.

If the system is running a 64 bit OS you should be running a 64 bit binary
and you should set the InnoDB Buffer pool to closer to 3200M... Additional
memory of something like 256M or maybe even 512M would work well...

If the system is running a 32 bit operating system (with a PIV it probably
is 32 bit) I've found that the best mix for us has been at 1850M/256M - that
won't break the memory limits of a 32 bit OS... You may need to adjust
slightly depending on your OS. I you're running a 32 bit OS having gobs and
gobs of ram isn't going to help a lot because you can't give InnoDB more
than 2Gbytes.

Of course if it is used for something other than MySQL then you clearly need
to keep some memory available for that too.

On our setup we don't use autoextend for the InnoDB data files, we make a
whole lot of 2000M data files (like 40 of them) - some Operating systems
don't deal well with large files - if your single InnoDB data file is a
little on the large side, then maybe (small chance) the issue is there...
Again that would probably affect more than just replication so probably
isn't the cause.

One of the things that affects replication is the network link between the
two servers, are they both connected at high speed with similar duplex
settings... Shouldn't be an issue as Replication isn't that hard on the
network resources, but if you were running one server at 100Mbit/Full Duplex
and the switch was running at a 100/half or something, weird things could be
happening. We've even seen setups where one side was set to Autonegotiate
and other side was set to 100/Full causing problems, because they end up at
10/Half on one side and 100/Full on the other, which gives pretty scary
network performance.

<no subject>Bruce Dembecki11 Feb