I got JMX counters hooked up to JConsole (couple of them opened).
Do you have any advice from your experience on what metrics I should focus on to spot this issue?
On Jul 9, 2012, at 22:19 PM, Stack wrote:
> On Mon, Jul 9, 2012 at 8:35 PM, Asaf Mesika <[EMAIL PROTECTED]> wrote:
>> My cluster started being incredibly slow in the past 2 days.
>> I've seen many Blocking updates on the region server logs, which lead me to believe HDFS creates is the bottleneck.
>> I ran a small test (hadoop fs -copyFromLocal big3_3Giga.tz.gz /tmp) which copies a 3.3G file, and I was surprised to see a rate of 11MB/sec, when it was previously around 28MB/sec.
>> I have 3 RS computers, hosting DataNode and embedded zookeeper as well.
>> And 1 Master computer, hosting NameNode as well.
>> The slowest computer has Core 2 Duo 2.93GHz, 4GB.
>> What steps can I take to find out the source of this slowdown?
> Install ganglia or opentsdb and figure what your cluster is up to when its slow.