So are you looking at the total process size (e.g. top) or are you looking at the amount of memory
the jvm says it is using (e.g. jmap -heap <pid>)?
If you are looking at the process size (top) jvm doesn't ever give memory back so over time the
process will just get bigger and bigger as it will spike in size before garbage collection can kick
in an free enough memory. If you are looking at jvm memory used then it will use the memory you
said + everything else "in flight". Stuff "in flight" includes any memory for the IPC running,
memory for return values, memory for compactions, memory for general bookkeeping, etc. The biggest
ones would be return values (and put values) for IPC and memory used for compactions.
~Jeff
On 11/1/2012 8:43 AM, 徐歷盛 wrote:
What's the usage of region server heap used memory ?
I originally thought it's roughly the sum of current memstore + blockcache
+ storefileindex. But in our environment, I have configured max heap to 20g
, heap used memory is sometimes up to 19g. At that moment, storefileindex
was 8g, blockcache was 1g, memstore was 1g. What's the rest 9g memory ?
Thanks in advance.
--
Jeff Whiting
Qualtrics Senior Software Engineer
je...@qualtrics.com
