Can anyone please help with the above questions? To summarise: 1) What is the impact of using mmap only for indices besides a degradation in read performance? 2) Why does the off heap consumed during Cassandra full repair remains occupied 12+ hours after the repair completion and is there a manual/configuration driven way to clear that earlier?
Thanks, Aman On Thu, 29 Jul, 2021, 6:47 pm Amandeep Srivastava, < amandeep.srivastava1...@gmail.com> wrote: > Hi Erick, > > Limiting mmap to index only seems to have resolved the issue. The max ram > usage remained at 60% this time. Could you please point me to the > limitations for setting this param? - For starters, I can see read > performance getting reduced up to 30% (CASSANDRA-8464 > <https://issues.apache.org/jira/browse/CASSANDRA-8464>) > > Also if you could please shed light on extended questions in my earlier > email. > > Thanks a lot. > > Regards, > Aman > > On Thu, Jul 29, 2021 at 12:52 PM Amandeep Srivastava < > amandeep.srivastava1...@gmail.com> wrote: > >> Thanks, Bowen, don't think that's an issue - but yes I can try upgrading >> to 3.11.5 and limit the merkle tree size to bring down the memory >> utilization. >> >> Thanks, Erick, let me try that. >> >> Can someone please share documentation relating to internal functioning >> of full repairs - if there exists one? Wanted to understand the role of the >> heap and off-heap memory separately during the process. >> >> Also, for my case, once the nodes reach the 95% memory usage, it stays >> there for almost 10-12 hours after the repair is complete, before falling >> back to 65%. Any pointers on what might be consuming off-heap for so long >> and can something be done to clear it earlier? >> >> Thanks, >> Aman >> >> >> > > -- > Regards, > Aman >
