thanks for the quick response and information again, Mikael! I keep thinking you all are
going to get sick of me.
regarding the processor resources devoted to network, do you know of a guide that explains
how to accomplish this on Linux? we have some hefty network cards in there (we can do
duplex gigabit if we need to) and we might as well use them to their maximum.
I'll be looking around for this info, but also thought you might know of something
> The bottleneck is in the network connection but not in its bandwidth
> but in its use of processor resources. Gigabit Enet only provides a
> solution when you have
> run out of bandwidth (which I don't think is the problem here). Giga
> Enet does provide some improvement to processor performance
> since there
> is one
> interrupt per 8k instead of per 1500 bytes.
> When scanning we can improve things somewhat by sending more
> records at
> a time. We are currently sending 16 at a time from the nodes.
> This is one optimisation we will need to do shortly, but also as I
> mentioned pushing filters to the ndbd nodes will improve
> performance by
> a great
> factor in those cases. Our experiments show that it goes from 120k
> records a second to 400-500k records per node. Unfortunately this
> is a bit complex so until it is in place we need to improve other
> things like the one above.
> We are also working with Dolphin Interconnect
> (www.dolphinics.no) that
> provides a socket implementation on a local network using proprietary
> that decreases the load on the processor which provides 3-4 times
> improvement in cases where network processing is bottleneck.
> This will
> documented in the MySQL manual shortly.
> Performance issues are getting incresed priority now that the MySQL
> integration works fairly good.
> It would be good to know which queries that you are going to use most
> commonly so that we get your
> input into which optimisations to prioritise.
> As an example is
> select count(*) from table
> a common one.
> select's not using indexes.
> Rgrds Mikael
> Mikael Ronström, Senior Software Architect
> MySQL AB, www.mysql.com