Cassandra exposes lot of metrics through Jconsole. You might be able to get some information from Jconsole.
On Wed, Sep 5, 2012 at 8:47 PM, Venkat Rama <venkata.s.r...@gmail.com>wrote: > Thanks for the quick reply, Mohit. Can we measure/monitor the size of > Hinted Handoffs? Would it be a good enough indicator of my back log? > > Although we know when a network is flaky, we are interested in knowing how > much data is piling up in local DC that needs to be transferred. > > Greatly appreciate your help. > > VR > > > On Wed, Sep 5, 2012 at 8:33 PM, Mohit Anchlia <mohitanch...@gmail.com>wrote: > >> As far as I know Cassandra doesn't use internal queueing mechanism >> specific to replication. Cassandra sends the write the remote DC and after >> that it's upto the tcp/ip stack to deal with buffering. If requests starts >> to timeout Cassandra would use HH upto certain time. For longer outage you >> would have to run repair. >> >> Also look at tcp/ip tuning parameters that are helpful with your scenario: >> >> http://kaivanov.blogspot.com/2010/09/linux-tcp-tuning.html >> >> Run iperf and test the latency. >> >> On Wed, Sep 5, 2012 at 8:22 PM, Venkat Rama <venkata.s.r...@gmail.com>wrote: >> >>> Hi, >>> >>> We have multi DC Cassandra ring with 2 DCs setup. We use LOCAL_QUORUM >>> for writes and reads. The network we have seen between the DC is sometimes >>> flaky lasting few minutes to few 10 of minutes. >>> >>> I wanted to know what is the best way to measure/monitor either the lag >>> or replication latency between the data centers. Are there any metrics I >>> can monitor to find the backlog of data that needs to be transferred? >>> >>> Thanks in advance. >>> >>> VR >>> >> >> >
