cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Harikrishnan Pillai <>
Subject Re: Java GC pauses, reality check
Date Mon, 28 Nov 2016 05:57:21 GMT
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



From: Kant Kodali <>
Sent: Saturday, November 26, 2016 8:39:01 PM
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 <<>>
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 Schr?der <<>>
> 2016-11-25 23:38 GMT+01:00 Kant Kodali <<>>:
>> 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.
> Best
>   Martin

View raw message