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From Yang <teddyyyy...@gmail.com>
Subject Re: What does a write lock ?
Date Thu, 07 Jul 2011 19:43:40 GMT
no , the memtable is a concurrentskiplistmap

insertion can happen in parallel
On Jul 7, 2011 9:24 AM, "Jeffrey Kesselman" <jeffpk@gmail.com> wrote:
> This has me more confused.
>
> Does this mean that ALL rows on a given node are only updated
sequentially,
> never in parallel?
>
> On Thu, Jul 7, 2011 at 3:21 PM, Yang <teddyyyy123@gmail.com> wrote:
>
>> just to add onto what jonathan said
>>
>> the columns are immutable . if u overwrite/ reconcile a new obj is
>> created and shoved into the memtable
>>
>> there is a shared lock for all writes though which guard against an
>> exclusive lock on memtable switching/flushing
>> On Jul 7, 2011 7:51 AM, "A J" <s5alye@gmail.com> wrote:
>> > Does a write lock:
>> > 1. Just the columns in question for the specific row in question ?
>> > 2. The full row in question ?
>> > 3. The full CF ?
>> >
>> > I doubt read does any locks.
>> >
>> > Thanks.
>>
>
>
>
> --
> It's always darkest just before you are eaten by a grue.

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