Quantcast

Getting " ParNew GC in ... CMS Old Gen ... " in logs

classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Getting " ParNew GC in ... CMS Old Gen ... " in logs

shahab
Hi,

I am keep getting following line in the cassandra logs, apparently something related to Garbage Collection. And I guess this is one of the signs why i do not get any response (i get time-out) when I query large volume of data ?!!! 

 ParNew GC in 248ms.  CMS Old Gen: 453244264 -> 570471312; Par Eden Space: 167712624 -> 0; Par Survivor Space: 0 -> 20970080

Is above line is indication of something that need to be fixed in the system?? how can I resolve this?


best,
/Shahab

Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Getting " ParNew GC in ... CMS Old Gen ... " in logs

Anuj
I think this is just saying that young gen collection using Par new collector took 248 seconds. This is quite normal with CMS unless it happens too frequenltly several times in a sec. I think query time has more to do with read timeout in yaml. Try increasing it. If its a range query then please increase range timeout in yaml. 

Thanks
Anuj Wadehra

Sent from Yahoo Mail on Android


From:"shahab" <[hidden email]>
Date:Mon, 20 Apr, 2015 at 9:59 pm
Subject:Getting " ParNew GC in ... CMS Old Gen ... " in logs

Hi,

I am keep getting following line in the cassandra logs, apparently something related to Garbage Collection. And I guess this is one of the signs why i do not get any response (i get time-out) when I query large volume of data ?!!! 

 ParNew GC in 248ms.  CMS Old Gen: 453244264 -> 570471312; Par Eden Space: 167712624 -> 0; Par Survivor Space: 0 -> 20970080

Is above line is indication of something that need to be fixed in the system?? how can I resolve this?


best,
/Shahab

Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Getting " ParNew GC in ... CMS Old Gen ... " in logs

Anuj
I meant 248 milli seconds

Sent from Yahoo Mail on Android


From:"Anuj Wadehra" <[hidden email]>
Date:Mon, 20 Apr, 2015 at 11:41 pm
Subject:Re: Getting " ParNew GC in ... CMS Old Gen ... " in logs

I think this is just saying that young gen collection using Par new collector took 248 seconds. This is quite normal with CMS unless it happens too frequenltly several times in a sec. I think query time has more to do with read timeout in yaml. Try increasing it. If its a range query then please increase range timeout in yaml. 

Thanks
Anuj Wadehra

Sent from Yahoo Mail on Android


From:"shahab" <[hidden email]>
Date:Mon, 20 Apr, 2015 at 9:59 pm
Subject:Getting " ParNew GC in ... CMS Old Gen ... " in logs

Hi,

I am keep getting following line in the cassandra logs, apparently something related to Garbage Collection. And I guess this is one of the signs why i do not get any response (i get time-out) when I query large volume of data ?!!! 

 ParNew GC in 248ms.  CMS Old Gen: 453244264 -> 570471312; Par Eden Space: 167712624 -> 0; Par Survivor Space: 0 -> 20970080

Is above line is indication of something that need to be fixed in the system?? how can I resolve this?


best,
/Shahab

Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Getting " ParNew GC in ... CMS Old Gen ... " in logs

Philo Yang
Only if there is a gc over more than 200ms it will be logged. You can use jstat to see whether each young gen gc takes so long like this, if so, you may need to reduce the size of young gen in conf/cassandra-env.sh to reduce the stopping time. Of course it will make the gc triggered more frequently so there is a trade off.

2015-04-21 2:23 GMT+08:00 Anuj Wadehra <[hidden email]>:
I meant 248 milli seconds

Sent from Yahoo Mail on Android


From:"Anuj Wadehra" <[hidden email]>
Date:Mon, 20 Apr, 2015 at 11:41 pm
Subject:Re: Getting " ParNew GC in ... CMS Old Gen ... " in logs

I think this is just saying that young gen collection using Par new collector took 248 seconds. This is quite normal with CMS unless it happens too frequenltly several times in a sec. I think query time has more to do with read timeout in yaml. Try increasing it. If its a range query then please increase range timeout in yaml. 

Thanks
Anuj Wadehra

Sent from Yahoo Mail on Android


From:"shahab" <[hidden email]>
Date:Mon, 20 Apr, 2015 at 9:59 pm
Subject:Getting " ParNew GC in ... CMS Old Gen ... " in logs

Hi,

I am keep getting following line in the cassandra logs, apparently something related to Garbage Collection. And I guess this is one of the signs why i do not get any response (i get time-out) when I query large volume of data ?!!! 

 ParNew GC in 248ms.  CMS Old Gen: 453244264 -> 570471312; Par Eden Space: 167712624 -> 0; Par Survivor Space: 0 -> 20970080

Is above line is indication of something that need to be fixed in the system?? how can I resolve this?


best,
/Shahab




--
Thanks,
Phil Yang

Loading...