We have also noticed a lot of MutationStage pending .
On Tue, 28 Jan 2020 at 11:06, Richard Andersen <rich...@andersenfamily.us> wrote: > I am in agreement with Patrick, this is a typical symptom of saturated IO. > Are there a high of drops and/or pending compactions? > > Get Outlook for Android <https://aka.ms/ghei36> > ------------------------------ > *From:* Patrick McFadin <pmcfa...@gmail.com> > *Sent:* Tuesday, January 28, 2020 11:25:49 AM > *To:* user@cassandra.apache.org <user@cassandra.apache.org> > *Subject:* Re: How to read content of hints file and apply them manually? > > Just to add in here. Any time I see any hints on a cluster, that's like > seeing smoke. If you can't explain it, you have a fire somewhere and it's > not going to get any better. > > By the few messages I've seen, I would start by looking at your IO > subsystem on your nodes. Do you have enough throughput to write and read at > the same time? These are exactly the symptoms I see when running Cassandra > on a SAN or NAS. > > Patrick > > On Mon, Jan 27, 2020 at 8:17 PM Surbhi Gupta <surbhi.gupt...@gmail.com> > wrote: > > We tried to tune sethintedhandoffthrottlekb to 100 , 1024 , 10240 but > nothing helped . > Our hints related parameters are as below, if you don't find any parameter > below then it is not set in our environment and should be of the default > value. > > max_hint_window_in_ms: 10800000 # 3 hours > > hinted_handoff_enabled: true > > hinted_handoff_throttle_in_kb: 100 > > max_hints_delivery_threads: 8 > > hints_directory: /var/lib/cassandra/hints > > hints_flush_period_in_ms: 10000 > > max_hints_file_size_in_mb: 128 > > On Mon, 27 Jan 2020 at 18:34, Jeff Jirsa <jji...@gmail.com> wrote: > > > The high cpu is probably the hints getting replayed slamming the write > path > > Slowing it down with the hint throttle may help > > It’s not instant. > > On Jan 27, 2020, at 6:05 PM, Erick Ramirez <flightc...@gmail.com> wrote: > > > > Increase the max_hint_window_in_ms setting in cassandra.yaml to more than > 3 hours, perhaps 6 hours. If the issue still persists networking may need > to be tested for bandwidth issues. > > > Just a note of warning about bumping up the hint window without > understanding the pros and cons. Be aware that doubling it means: > > - you'll end up doubling the size of stored hints in > the hints_directory > - there'll be twice as much hints to replay when node(s) come back > online > > There's always 2 sides to fiddling with the knobs in C*. Cheers! > >
