Re: Memtable tuning in 1.0 and higher

2012-07-04 Thread aaron morton
Joost, Part of Jonathans explanation for flushing every approx 5 minutes was to reduce the size of the commit log, and reduce the replay time. Even with the patch flushing memtables is necessary at some point to truncate the log. If this is an issue consider disabling

Re: Memtable tuning in 1.0 and higher

2012-07-02 Thread Jonathan Ellis
I'm afraid not. It's too much change for an oldstable release series, and the bulk of the change is to AtomicSortedColumns which doesn't exist in 1.0, so even if we wanted to take a maybe it's okay if we release it first in 1.1.3 and then backport approach it wouldn't improve our safety margin

Re: Memtable tuning in 1.0 and higher

2012-07-01 Thread Jonathan Ellis
On Thu, Jun 28, 2012 at 1:39 PM, Joost van de Wijgerd jwijg...@gmail.com wrote: the currentThoughput is increased even before the data is merged into the memtable so it is actually measuring the throughput afaik. You're right. I've attached a patch to

Re: Memtable tuning in 1.0 and higher

2012-07-01 Thread Joost Van De Wijgerd
Hi Jonathan, Looks good, any chance of porting this fix to the 1.0 branch? Kind regards Joost Sent from my iPhone On 1 jul. 2012, at 09:25, Jonathan Ellis jbel...@gmail.com wrote: On Thu, Jun 28, 2012 at 1:39 PM, Joost van de Wijgerd jwijg...@gmail.com wrote: the currentThoughput is

Re: Memtable tuning in 1.0 and higher

2012-06-28 Thread Jonathan Ellis
[moving to user list] 1.0 doesn't care about throughput or op count anymore, only whether the total memory used by the *currrent* data in the memtables has reached the global limit. So, it automatically doesn't count historical data that's been overwritten in the current memtable. So, you may

Re: Memtable tuning in 1.0 and higher

2012-06-28 Thread Edward Capriolo
I was wondering if we could find cases where the new one global limit would not be good for some. As Jonathan said setting you memtable memory high will help. Although if you are constantly overwtiting the exact almost same data it should never flush if you have enough dedicated memory. On

Re: Memtable tuning in 1.0 and higher

2012-06-28 Thread Joost van de Wijgerd
Hi Jonathan, The problem is not that I haven't allocated enough memory to the memtables, the problem is that the memtable for this particular CF flushes too early because the liveRation stays at 1.0. When looking at the code it seems to me the the liveRatio is calculated based on the throughput