<Do you have 9.5TB on a single node ?> In the normal case it's best to have around 300 to 500GB per node. With that much data is will take a week to run repair or replace a failed node.
Hi Aaron - This was true for pre 1.2 but with 1.2 and virtual nodes, does this still hold ? 1 TB at 1Gb/s will take roughly 2.2hrs assume we stream from say 100 nodes... From: aaron morton [mailto:aa...@thelastpickle.com] Sent: 06 March 2013 23:47 To: user@cassandra.apache.org Subject: Re: Hinted handoff Check the IO utilisation using iostat You *really* should not need to make HH run faster, if you do there is some thing bad going on. I would consider dropping the hints and running repair. Data is ~9.5 TB Do you have 9.5TB on a single node ? In the normal case it's best to have around 300 to 500GB per node. With that much data is will take a week to run repair or replace a failed node. Cheers ----------------- Aaron Morton Freelance Cassandra Developer New Zealand @aaronmorton http://www.thelastpickle.com On 6/03/2013, at 1:22 PM, Kanwar Sangha <kan...@mavenir.com<mailto:kan...@mavenir.com>> wrote: Is this correct ? I have Raid 0 setup for 16 TB across 8 disks. Each disk is 7.2kRPM with IOPS of 80 per disk. Data is ~9.5 TB So 4K * 80 * 9.5 = 3040 KB ~ 23.75 Mb/s. So basically I am limited at the disk rather than the n/w From: Kanwar Sangha [mailto:kan...@mavenir.com<http://mavenir.com>] Sent: 06 March 2013 15:11 To: user@cassandra.apache.org<mailto:user@cassandra.apache.org> Subject: RE: Hinted handoff After trying to bump up the "hinted_handoff_throttle_in_kb" to 1G/b per sec, It still does not go above 25Mb/s. Is there a limitation ? From: Kanwar Sangha [mailto:kan...@mavenir.com] Sent: 06 March 2013 14:41 To: user@cassandra.apache.org<mailto:user@cassandra.apache.org> Subject: RE: Hinted handoff Got the param. thanks From: Kanwar Sangha [mailto:kan...@mavenir.com] Sent: 06 March 2013 13:50 To: user@cassandra.apache.org<mailto:user@cassandra.apache.org> Subject: Hinted handoff Hi - Is there a way to increase the hinted handoff throughput ? I am seeing around 8Mb/s (bits). Thanks, Kanwar
