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From Héctor Izquierdo Seliva <izquie...@strands.com>
Subject Re: Tombstones and memtable_operations
Date Tue, 19 Apr 2011 20:25:23 GMT

El mié, 20-04-2011 a las 08:16 +1200, aaron morton escribió:
> I think their may be an issue here, we are counting the number of columns in the operation.
When deleting an entire row we do not have a column count. 
> 
> Can you let us know what version you are using and how you are doing the delete ? 
> 
> Thanks
> Aaron
> 

I'm using 0.7.4. I have a file with all the row keys I have to delete
(around 100 million) and I just go through the file and issue deletes
through pelops. 

Should I manually issue flushes with a cron every x time?

> On 20 Apr 2011, at 04:21, Héctor Izquierdo Seliva wrote:
> 
> > Ok, I've read about gc grace seconds, but i'm not sure I understand it
> > fully. Untill gc grace seconds have passed, and there is a compaction,
> > the tombstones live in memory? I have to delete 100 million rows and my
> > insert rate is very low, so I don't have a lot of compactions. What
> > should I do in this case? Lower the major compaction threshold and
> > memtable_operations to some very low number?
> > 
> > Thanks
> > 
> > El mar, 19-04-2011 a las 17:36 +0200, Héctor Izquierdo Seliva escribió:
> >> Hi everyone. I've configured in one of my column families
> >> memtable_operations = 0.02 and started deleting keys. I have already
> >> deleted 54k, but there hasn't been any flush of the memtable. Memory
> >> keeps pilling up and eventually nodes start to do stop-the-world GCs. Is
> >> this the way this is supposed to work or have I done something wrong?
> >> 
> >> Thanks!
> >> 
> > 
> > 
> 



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