for what it's worth i've been having pretty good success using the
Datastax AMIs.
On 5/17/2012 6:59 PM, koji Lin wrote:
Hi
We use amazon ami 3.2.12-3.2.4.amzn1.x86_64
and some of our data file are more than 10G
thanks
koji
2012-5-16 下午6:00 於 "aaron morton" <aa...@thelastpickle.com
<mailto:aa...@thelastpickle.com>> 寫道：
On Ubuntu ? Sounds like
http://wiki.apache.org/cassandra/FAQ#ubuntu_hangs
Cheers
-----------------
Aaron Morton
Freelance Developer
@aaronmorton
http://www.thelastpickle.com
On 16/05/2012, at 2:13 PM, koji Lin wrote:
Hi
Our service already run cassandra 1.0 on 1x ec2 instances(with
ebs), and we saw lots of discussion talk about using
ephemeral raid for better performance and consistent performance.
So we want to create new instance using 4 ephemeral raid0, and
copy the data from ebs to finally replace the old instance and
reduce some .
we create the xlarge instance with -b '/dev/sdb=ephemeral0' -b
'/dev/sdc=ephemeral1' -b '/dev/sdd=ephemeral2' -b
'/dev/sde=ephemeral3',
and use mdadm command like this mdadm --create /dev/md0
--level=0 -c256 --raid-devices=4 /dev/sdb /dev/sdc /dev/sdd /dev/sde
after copying file and start the cassandra(same token as old
instance it replaced).
we saw the read is really fast always keep 2xxm/sec, but system
load exceed 40, with high iowait, and lots of client get timeout
result. We guess maybe it's the problem of ec2 instance, so we
create another one with same setting to replace other machine
,but the result is same . Then we rollback to ebs with single
disk ,read speed keeps at 1xmb/sec but system becomes well
.(using ebs with 2 disks raid0 will keep at 2xmb/sec and higher
iowait then single disk ,but still works)
Is there anyone meet the same problem too ? or do we forget
something to configure?
thank you
koji
