There are more items then data in the BlockCache. There are bloom filters,
indexes, and data. You should look at your blockCacheHitCount for each of
these item times. You may have a high hit rate on blooms, but low on data
for example.
The fsRead metrics are for items that read from disk. Not item
I am on EC2, with HBase 0.94.2 and I can't find an explanation to this
phenomena:
I'm having these metrics on my RegionServers:
blockCacheHitRatio=87%
fsReadLatencyHistogramMean= 5886103.47
fsReadLatencyHistogramMedian=6280445
fsReadLatencyHistogram75th= 28117916.5
fsReadLatencyHistogram95th= 536
