I was hitting the same problem last days so i went through some test,
the configuration you suggest is quite nice and according to my result
yun anticipated me on the problem doing my next step ;).<br><br>basicly
i was wondering using MySQL Cluster and a Cluster MySQL for some
different services. Setting the point that mysql cluster was taken in
account for availability specs more than for its performance.<br>
<br>That said here some spec data:<br><br>hp/ibm dual quadcore with SAS RAID and 8GB of RAM. (for dom0)<br>OS: Centos 5.3<br>Virtualization: xen<br><br>for real server no SAS but SATA RAID and 4GB of RAM<br><br>I got 4 of the former and 2 of the latter.<br>
All domus where on .img files.<br><br>Used sysbench for testing <br><br>i tested: mysql cluster on domUs, mysql on domu and mysql on real server <br><br>I got real pour performance with mysql cluster on domus no data for that, but no optimiziation was done.<br>
<br>Moreover consider that no optimizatino was done for none of the configurations.<br><br>No conclusion at all, more serious efforts can be done for getting the best from each donfiguration, so just get this datas as a non production test, which is what it is.<br>
<br>Here some numbers hope they are usefull:<br><br>***************************Mysql cluster on real server (SATA + 4GB) ********************<br>sysbench --num-threads=4 --max-requests=20000 --test=oltp --mysql-db=sbtest --mysql-user=test --mysql-password=*********** --mysql-host=************** --mysql-port=********* --mysql-table-engine=ndbcluster --oltp-test-mode=complex run<br>
<br>OLTP test statistics:<br> queries performed:<br> read: 280000<br> write: 100000<br> other: 40000<br> total: 420000<br>
transactions: 20000 (440.95 per sec.)<br> deadlocks: 0 (0.00 per sec.)<br> read/write requests: 380000 (8378.12 per sec.)<br> other operations: 40000 (881.91 per sec.)<br>
<br>Test execution summary:<br> total time: 45.3563s<br> total number of events: 20000<br> total time taken by event execution: 181.2726<br> per-request statistics:<br> min: 5.72ms<br>
avg: 9.06ms<br> max: 154.81ms<br> approx. 95 percentile: 10.30ms<br><br>Threads fairness:<br> events (avg/stddev): 5000.0000/2.74<br>
execution time (avg/stddev): 45.3182/0.00<br><br><br>******************** Plain Mysql on xen domu *************************<br>OLTP test statistics:<br> queries performed:<br> read: 280000<br>
write: 100000<br> other: 40000<br> total: 420000<br> transactions: 20000 (368.68 per sec.)<br>
deadlocks: 0 (0.00 per sec.)<br> read/write requests: 380000 (7004.93 per sec.)<br> other operations: 40000 (737.36 per sec.)<br><br>Test execution summary:<br>
total time: 54.2475s<br> total number of events: 20000<br> total time taken by event execution: 216.8328<br> per-request statistics:<br> min: 6.35ms<br>
avg: 10.84ms<br> max: 263.48ms<br> approx. 95 percentile: 11.14ms<br><br>Threads fairness:<br> events (avg/stddev): 5000.0000/2.45<br>
execution time (avg/stddev): 54.2082/0.00<br><br><br>******************* Finally mysql on real server (SATA + 4GB) ***************<br>OLTP test statistics:<br> queries performed:<br> read: 280000<br>
write: 100000<br> other: 40000<br> total: 420000<br> transactions: 20000 (467.17 per sec.)<br>
deadlocks: 0 (0.00 per sec.)<br> read/write requests: 380000 (8876.18 per sec.)<br> other operations: 40000 (934.33 per sec.)<br><br>Test execution summary:<br>
total time: 42.8112s<br> total number of events: 20000<br> total time taken by event execution: 171.0977<br> per-request statistics:<br> min: 5.67ms<br>
avg: 8.55ms<br> max: 133.64ms<br> approx. 95 percentile: 9.84ms<br><br>Threads fairness:<br> events (avg/stddev): 5000.0000/2.55<br>
execution time (avg/stddev): 42.7744/0.00<br><br><br><div class="gmail_quote">2010/1/15 compdoc <span dir="ltr"><<a href="mailto:compdoc@hotrodpc.com">compdoc@hotrodpc.com</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div><div></div><div class="h5">-----Original Message-----<br>
Fhttp://<a href="http://www.liveleak.com/view?i=375_1263347833rom" target="_blank">www.liveleak.com/view?i=375_1263347833rom</a>:<br>
<a href="mailto:centos-virt-bounces@centos.org">centos-virt-bounces@centos.org</a><br>
[mailto:<a href="mailto:centos-virt-bounces@centos.org">centos-virt-bounces@centos.org</a>] On Behalf Of Ben M.<br>
Sent: Friday, January 15, 2010 8:56 AM<br>
To: Discussion about the virtualization on CentOS<br>
Subject: Re: [CentOS-virt] Xen Database vms<br>
<br>
Neil:<br>
<br>
What if it were the only "real" active vm? I know that might<br>
sound a bit<br>
of a waste, but I am really enjoying the backup and<br>
duplication<br>
abilities of running in a Xen hypervisor as well as its<br>
other features.<br>
It seems to be saving me a lot of time in production<br>
settings. And there<br>
is also a comfort level in uniformity on a LAN.<br>
<br>
Would there still be a significant hit on resource<br>
performance by the<br>
hypervisor if running that database server alone in it, or<br>
alongside a<br>
few rarely used, lightweight or spurious vms? I am talking<br>
about the<br>
database activities running during the biz day and backups,<br>
batches and<br>
other maintenance in the off hours. Nothing urgent here,<br>
just trying to<br>
plan out the future, mull over the possibilities and where<br>
to head.<br>
<br>
- Ben<br>
</div></div>-----Original Message-----<br>
<br>
<br>
<br>
I think it could work well. Having a server in a vm makes it<br>
more portable.<br>
<br>
Many of my servers and services are running in vms on two<br>
centos 5.4 servers: openfiler, efw firewall, trixbox 2.8,<br>
SME Server (in server mode for email and spamassassin),<br>
windows 2003 server, windows 2008 server, windows 7, and<br>
others that aren't running.<br>
<br>
I would suggest:<br>
<br>
If there are a lot of temp files or disk access to the OS,<br>
install the vm OS on a block device rather than to a file.<br>
The storage should be on a local block device as well.<br>
<br>
If there's a lot of lan traffic to/from the other vms,<br>
install a 3rd ethernet card in the server that is only used<br>
for db traffic.<br>
<br>
I also use a virtual network that the vms can use to reach<br>
each other. This is basically a private internal lan running<br>
across the host machine's buses, rather than through your<br>
network switch.<br>
<br>
I get native performance with my set up...<br>
<div><div></div><div class="h5"><br>
<br>
<br>
_______________________________________________<br>
CentOS-virt mailing list<br>
<a href="mailto:CentOS-virt@centos.org">CentOS-virt@centos.org</a><br>
<a href="http://lists.centos.org/mailman/listinfo/centos-virt" target="_blank">http://lists.centos.org/mailman/listinfo/centos-virt</a><br>
</div></div></blockquote></div><br>