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From Tatu Saloranta <tsalora...@gmail.com>
Subject Re: Overwhelming a cluster with writes?
Date Tue, 06 Apr 2010 17:58:32 GMT
On Tue, Apr 6, 2010 at 8:17 AM, Jonathan Ellis <jbellis@gmail.com> wrote:
> On Tue, Apr 6, 2010 at 2:13 AM, Ilya Maykov <ivmaykov@gmail.com> wrote:
>> That does sound similar. It's possible that the difference I'm seeing
>> between ConsistencyLevel.ZERO and ConsistencyLevel.ALL is simply due
>> to the fact that using ALL slows down the writers enough that the GC
>> can keep up.
>
> No, it's mostly due to ZERO meaning "buffer this locally and write it
> when it's convenient," and buffering takes memory.  If you check your
> tpstats you will see the pending ops through the roof on the node
> handling the thrift connections.
>

This sounds like a great FAQ entry? (apologies if it's already included)
So that ideally users would only use this setting if they (think they)
know what they are doing. :-)

-+ Tatu +-

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