AFAIk this is still roughly correct
http://thelastpickle.com/2011/04/28/Forces-of-Write-and-Read/
It includes information on the page size read from disk.
Cheers
-
Aaron Morton
Freelance Cassandra Developer
New Zealand
@aaronmorton
http://www.thelastpickle.com
On 22/02/2013,
Hi,
On Feb 21, 2013, at 7:52 , Kanwar Sangha wrote:
> Hi – Can someone explain the worst case IOPS for a read ? No key cache, No
> row cache, sampling rate say 512.
>
> 1) Bloom filter will be checked to see existence of key (In RAM)
> 2) Index filer sample (IN RAM) will be checked
...@scode.org [mailto:sc...@scode.org] On Behalf Of Peter Schuller
Sent: 21 February 2013 00:05
To: user@cassandra.apache.org
Subject: Re: Read IO
> Is this correct ?
Yes, at least under optimal conditions and assuming a reasonably sized row.
Things like read-ahead (at the kernel level) will play i
> Is this correct ?
Yes, at least under optimal conditions and assuming a reasonably sized
row. Things like read-ahead (at the kernel level) will play into it;
and if your read (even if assumed to be small) straddles two pages you
might or might not take another read depending on your kernel setti
