Hi all,
I encounter a problem about long gc pause cause the region server's local
zookeeper client cannot send heartbeats, the session times out.
But I want to know why the HBase master sends a MSG_REGIONSERVER_STOP op to
region sever to stop its services rather than reinitialize a new zookeepe
On Tue, Dec 28, 2010 at 6:59 PM, ChingShen wrote:
> But I want to know why the HBase master sends a MSG_REGIONSERVER_STOP op to
> region sever to stop its services rather than reinitialize a new zookeeper
> client or restart region server?
>
Can I see more regionserver log? If session expired,
Hi St.Ack,
Please see the attach file, and there are 3 RS/DN/TT + 1 MS/NN/JT in my
cluster. (Hadoop-0.20.2, HBase 0.20.6)
Thanks.
Shen
On Wed, Dec 29, 2010 at 1:34 PM, Stack wrote:
> On Tue, Dec 28, 2010 at 6:59 PM, ChingShen
> wrote:
> > But I want to know why the HBase master sends a MS
OK. There is nothing enlightening there. There didn't seem to be
master log in the attachment? I should have asked you include that.
I see that one server thought the filesystem had gone away. Did you
pull HDFS out from under it at around this time per chance?
St.Ack
On Tue, Dec 28, 2010 at 1
Shen,
It's a design decision, and we historically preferred to let cluster
managers decide whether they want to restart the processes that died
or investigate why it has died then decide on what they want to do.
You can easily write tools that will restart the region servers if
they die, but the f
Hi J-D,
Yes, I run a MR job on my cluster, and when I set the MR configs as below
that long gc pause is occurred.
MR config: (4-core cpu per RS/DN/TT node)
mapred.tasktracker.reduce.tasks.maximum = 3
mapred.tasktracker.map.tasks.maximum = 4
mapred.reduce.slowstart.completed.maps = 0.05
Your MR job is likely generating a lot of IO and possibly starving
HBase while it's running (it would require some monitoring on your end
to figure that out). Less tasks per machine will leave more breathing
room, there's not that many ways to unload overloaded machines.
J-D
On Fri, Jan 7, 2011 a