Hi @Kant Kodali, 11 /11 , 11 nodes in DC1 and 11 nodes in DC2.
________________________________ From: Kant Kodali <k...@peernova.com> Sent: Monday, November 28, 2016 6:56 AM To: user@cassandra.apache.org Subject: Re: Java GC pauses, reality check Hi Hari, I am a little bit confused. What you mean 11/11 ? "We are using g1GC in most clusters with 26GB heap and extra threads given to parallel and old gen collection. Those clusters 99% is also under 5 ms and doing good". So with G1GC you are able get under 5ms not the C4 (Zing's Garbage Collector?) What timeouts are you referring to here? Thanks, kant On Sun, Nov 27, 2016 at 9:57 PM, Harikrishnan Pillai <hpil...@walmartlabs.com<mailto:hpil...@walmartlabs.com>> wrote: Hi @Kant Kodali, We have multiple clusters running zing . One cluster has 11/11 and another one also has 11/11.(190 GB mem,6TB hard disk and 16 Physical core machines) The average read size is around 200KB and it can go upto 6 MB. We are using g1GC in most clusters with 26GB heap and extra threads given to parallel and old gen collection. Those clusters 99% is also under 5 ms and doing good. We used Zing to remove all timeouts . If application is not having that requirement G1GC is good. with g1gGC i have seen average 200-300 ms min pauses every 4 minutes and 600 ms pauses every 6 hours and 99% latency is under 5-10 ms for most of the clusters having 10- 100 KB of read data. Regards Hari ________________________________ From: Kant Kodali <k...@peernova.com<mailto:k...@peernova.com>> Sent: Saturday, November 26, 2016 8:39:01 PM To: user@cassandra.apache.org<mailto:user@cassandra.apache.org> Subject: Re: Java GC pauses, reality check @Harikrishnan Pillai: How many nodes you guys are running? and what is an approximate read size and an approximate write size? On Fri, Nov 25, 2016 at 7:32 PM, Harikrishnan Pillai <hpil...@walmartlabs.com<mailto:hpil...@walmartlabs.com>> wrote: We are running azul zing in prod with 1 million reads/s and 100 K writes/s with azul .we never had a major gc above 10 ms . Sent from my iPhone > On Nov 25, 2016, at 3:49 PM, Martin Schröder > <mar...@oneiros.de<mailto:mar...@oneiros.de>> wrote: > > 2016-11-25 23:38 GMT+01:00 Kant Kodali > <k...@peernova.com<mailto:k...@peernova.com>>: >> I would also restate the following sentence "java GC pauses are pretty much >> a fact of life" to "Any GC based system pauses are pretty much a fact of >> life". >> >> I would be more than happy to see if someone can counter prove. > > Azul disagrees. > https://www.azul.com/products/zing/pgc/ > > Best > Martin