disk_acces_mode = mmap_index_only to use fewer maps (or disable it entirely as appropriate).
On Thu, Apr 15, 2021 at 4:42 PM Kane Wilson <k...@raft.so> wrote: > Cassandra mmaps SSTables into memory, of which there can be many files > (including all their indexes and what not). Typically it'll do so greedily > until you run out of RAM. 65k map areas tends to be quite low and can > easily be exceeded - you'd likely need very low density nodes to avoid > going over 65k, and thus you'd require lots of nodes (making management > harder). I'd recommend figuring out a way to up your limits as the first > course of action. > > raft.so - Cassandra consulting, support, and managed services > > > On Fri, Apr 16, 2021 at 4:29 AM Jai Bheemsen Rao Dhanwada < > jaibheem...@gmail.com> wrote: > >> Hello All, >> >> The recommended settings for Cassandra suggests to have a higher value >> for vm.max_map_count than the default 65530 >> >> WARN [main] 2021-04-14 19:10:52,528 StartupChecks.java:311 - Maximum >>> number of memory map areas per process (vm.max_map_count) 65530 is too >>> low, recommended value: 1048575, you can change it with sysctl. >> >> >> However, I am running Cassandra process as a container, where I don't >> have access to change the value on Kubernetes worker node and the cassandra >> pod runs with less privileges. I would like to understand why Cassandra >> needs a higher value of memory map? and is there a way to restrict >> Cassandra to not use beyond the default value of 65530. If there is a way >> please let me know how to restrict and also any side effects in making that >> change? >> >> Thanks in advance >> >
