Hi, What's the best way to monitor / know how's bucket cache being used, how much stuff is cached there, etc?
Our RegionServer can use 32G of heap size, so we exported HBASE_OFFHEAPSIZE to 24G in hbase-env.sh, set hfile.block.cache.size to 0.05, and set couple of block sizes that we know we are using knowing our usage patterns. And this is where strange part starts - in web UI we see now, with turning this off, with those values, that total BlockCache available is 1G - before it was 10G. What we basically tried to achieve was to double it to 20G. Documentation we were referring to was http://www.cloudera.com/content/cloudera/en/documentation/core/latest/topics/admin_hbase_blockcache_configure.html#concept_cp3_fhy_dr_unique_1__section_m3r_2cz_dr_unique_1 as HBase book is not going into too much details how to properly configure this and get what you want. Btw. if we put hfile.block.cache.size to 0.2 we see in web UI that total available cache is 24G, but then after some time we had region server crashing. Host server have enough RAM, considering only data node and region server running there (128G of RAM in total) so we thought we could increase caching with turning on this functionality. Do you maybe see what exactly we are doing wrong? How to exactly increase offheap caching - and is it possible to monitor it anyhow, as in metrics we don't see anything associating to it? Thanks, Dejan
