On Wednesday, July 17, 2013 6:08 PM Ants Aasma wrote: > On Wed, Jul 17, 2013 at 2:54 PM, Amit Kapila <amit.kap...@huawei.com> > wrote: > > I think Oracle also use similar concept for making writes efficient, > and > > they have patent also for this technology which you can find at below > link: > > > http://www.google.com/patents/US7194589?dq=645987&hl=en&sa=X&ei=kn7mUZ- > PIsWq > > rAe99oDgBw&sqi=2&pjf=1&ved=0CEcQ6AEwAw > > > > Although Oracle has different concept for performing checkpoint > writes, but > > I thought of sharing the above link with you, so that unknowingly we > should > > not go into wrong path. > > > > AFAIK instead of depending on OS buffers, they use direct I/O and > infact in > > the patent above they are using temporary buffer (Claim 3) to sort > the > > writes which is not the same idea as far as I can understand by > reading > > above thread. > > They are not even sorting anything, the patent is for > opportunistically looking for adjacent dirty blocks when writing out a > dirty buffer to disk. While a useful technique, this has nothing to do > with sorting checkpoints.
It is not sorting, rather it finds consecutive blocks before writing to disk using hashing in buffer cache. I think the patch is different from it in multiple ways. I had read this patent some time back and thought that you are also trying to achieve something similar (Reduce random I/O), so shared with you. With Regards, Amit Kapila. -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers