z11373 wrote:
I recall that I ever read somewhere that Accumulo is able to move tablets to
other tservers if it experiences high load (i.e. read request) on one
particular tserver, is that correct?
No, we don't rebalance tablet assignments on load. I believe the default
balancer implementation tries to spread tablets for a specific table
evenly across the available nodes. This is a pluggable implementation.
From the monitor page, one of the tservers that got heavy request would have
at most 16 active scans, and often 3 digit number inside the parenthesis
(i.e. # of scans waiting). I want to experiment if changing the max active
scans would help the test run faster. Is it possible to change that max
active scans number from 16 to a higher number?
Try increasing the following properties (I provided their defaults for you):
tserver.readahead.concurrent.max=16
tserver.scan.files.open.max=100
I remember writing up some really thorough documentation on how to use
the configuration properties we have to really saturate your nodes, but
I don't remember where that was. I'll try to find it :)
You can double check the Accumulo user manual on the website to see if
we have some information there (that should be where we have the info).
