[
https://issues.apache.org/jira/browse/CASSANDRA-629?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Stu Hood updated CASSANDRA-629:
-------------------------------
Attachment: 629-2-use-xor-in-merkletree.diff
629-1-utility-changes.diff
After benchmarking and trying to optimize the current code as much as possible,
I gave up on trying to generate the full range down to hash depth.
Jun suggested using XOR on 193, both for speed and simplicity, but I was
worried about hash collisions. In order to make using XOR a little more secure,
I bumped the digests we generate in AEService to SHA-256, so that we minimize
the chance of collision as much as possible.
Time to validate 1 million rows dropped from 84 seconds to 1.9 seconds
(including hashing).
> antientropyservice patchset nearly doubles compaction time
> ----------------------------------------------------------
>
> Key: CASSANDRA-629
> URL: https://issues.apache.org/jira/browse/CASSANDRA-629
> Project: Cassandra
> Issue Type: Bug
> Components: Core
> Reporter: Jonathan Ellis
> Assignee: Stu Hood
> Fix For: 0.5
>
> Attachments: 629-1-utility-changes.diff,
> 629-2-use-xor-in-merkletree.diff
>
>
> CompactionsTest goes from 2.9s to 5.7s for me, before/after the 193 patchset.
> This is not an acceptable speed hit for when no repair work is actually
> being done, assuming it is representative of "real" compactions.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
