My default is G1GC using 50% of available RAM (so typically a minimum of 16 GB for the JVM). That has worked in just about every case I’m familiar with. In the old days we used CMS, but tuning that beast is a black art with few wizards available (though several on this mailing list). Today, I just don’t see GC issues – unless there is a bad query in play. For me, the data model/query construction is the more fruitful path to achieving performance and reliability.
Sean Durity From: Jon Haddad <j...@jonhaddad.com> Sent: Tuesday, March 19, 2019 2:16 PM To: user@cassandra.apache.org Subject: [EXTERNAL] Re: Garbage Collector G1 is optimized for high throughput with higher pause times. It's great if you have mixed / unpredictable workloads, and as Elliott mentioned is mostly set & forget. ZGC requires Java 11, which is only supported on trunk. I plan on messing with it soon, but I haven't had time yet. We'll share the results on our blog (TLP) when we get to it. Jon On Tue, Mar 19, 2019 at 10:12 AM Elliott Sims <elli...@backblaze.com<mailto:elli...@backblaze.com>> wrote: I use G1, and I think it's actually the default now for newer Cassandra versions. For G1, I've done very little custom config/tuning. I increased heap to 16GB (out of 64GB physical), but most of the rest is at or near default. For the most part, it's been "feed it more RAM, and it works" compared to CMS's "lower overhead, works great until it doesn't" and dozens of knobs. I haven't tried ZGC yet, but anecdotally I've heard that it doesn't really match or beat G1 quite yet. On Tue, Mar 19, 2019 at 9:44 AM Ahmed Eljami <ahmed.elj...@gmail.com<mailto:ahmed.elj...@gmail.com>> wrote: Hi Folks, Does someone use G1 GC or ZGC on production? Can you share your feedback, the configuration used if it's possible ? Thanks. ________________________________ The information in this Internet Email is confidential and may be legally privileged. It is intended solely for the addressee. Access to this Email by anyone else is unauthorized. If you are not the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it, is prohibited and may be unlawful. When addressed to our clients any opinions or advice contained in this Email are subject to the terms and conditions expressed in any applicable governing The Home Depot terms of business or client engagement letter. The Home Depot disclaims all responsibility and liability for the accuracy and content of this attachment and for any damages or losses arising from any inaccuracies, errors, viruses, e.g., worms, trojan horses, etc., or other items of a destructive nature, which may be contained in this attachment and shall not be liable for direct, indirect, consequential or special damages in connection with this e-mail message or its attachment.
