Ok, thanks I'll give that a try.

What does small_file_threshold do then?

- Jeremy


On Wed, Sep 14, 2011 at 12:48 PM, Dan Reverri <[email protected]> wrote:

> Hi Jeremy,
>
> The max_file_size parameter controls when Bitcask will close the currently
> active data file and start a new data file. The active data file will not be
> considered when determining if a merge should occur. The default
> max_file_size is 2GBs. This means that each partition in the system can grow
> to 2GBs before the data files are considered for merging. This is likely
> what you are seeing in your situation.
>
> You can lower the max_file_size in the app.config file under the bitcask
> section. This parameter should be specified in bytes.
>
> This article is related to your issue:
>
> https://help.basho.com/entries/20141178-why-does-it-seem-that-bitcask-merging-is-only-triggered-when-a-riak-node-is-restarted
>
> Thanks,
> Dan
>
> Daniel Reverri
> Developer Advocate
> Basho Technologies, Inc.
> [email protected]
>
>
>
> On Wed, Sep 14, 2011 at 8:49 AM, Jeremy Raymond <[email protected]>wrote:
>
>> If I'm reading the docs correctly, only files smaller
>> than small_file_threshold will be included in a merge. So
>> if small_file_threshold must be bigger than max_file_size for a merge to
>> happen?
>>
>>  - Jeremy
>>
>>
>>
>> On Wed, Sep 14, 2011 at 10:23 AM, Jeremy Raymond <[email protected]>wrote:
>>
>>> Maybe I just need to tweak the Bitcask parameters to merge more often?
>>>
>>> I have approx 17000 keys which get overwritten once an hour. After each
>>> updated the /var/lib/riak/bitcask folder grows by 20 MB (so about 1200 bytes
>>> per key). With the default frag_merge_trigger at 60 I should get a merge
>>> every 3 hours as I would have > 60% of the keys being dead? This would also
>>> meet the default frag_threshold of 40 since > 40% of the keys are dead? I'm
>>> not seeing the merging happening.
>>>
>>> - Jeremy
>>>
>>>
>>>
>>> On Wed, Sep 14, 2011 at 9:28 AM, Jeremiah Peschka <
>>> [email protected]> wrote:
>>>
>>>> I would think that the InnoDB backend would be a better backend for the
>>>> use case you're describing.
>>>> ---
>>>> Jeremiah Peschka - Founder, Brent Ozar PLF, LLC
>>>> Microsoft SQL Server MVP
>>>>
>>>> On Sep 14, 2011, at 8:09 AM, Jeremy Raymond wrote:
>>>>
>>>> > Hi,
>>>> >
>>>> > I store data in Riak whose keys constantly get overwritten with new
>>>> data. I'm currently using Bitcask as the back-end and recently noticed the
>>>> Bitcask data folder grow to 24GB. After restarting the nodes, which I think
>>>> triggered Bitcask merge, the data went down to 96MB. Today the data dirs 
>>>> are
>>>> back up to around 500MB. Would an alternate backend better suit this type 
>>>> of
>>>> use case where keys are constantly being overwritten?
>>>> >
>>>> > - Jeremy
>>>> > _______________________________________________
>>>> > riak-users mailing list
>>>> > [email protected]
>>>> > http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
>>>>
>>>>
>>>
>>
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>>
>
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