Re: making file system block size bigger to improve hdfs performance ?

2011-10-10 Thread Steve Loughran
On 09/10/11 07:01, M. C. Srivas wrote: If you insist on HDFS, try using XFS underneath, it does a much better job than ext3 or ext4 for Hadoop in terms of how data is layed out on disk. But its memory footprint is alteast twice of that of ext3, so it will gobble up a lot more memory on your

Re: making file system block size bigger to improve hdfs performance ?

2011-10-10 Thread M. C. Srivas
XFS was created in 1991 by Silicon Graphics. It was designed for streaming. The Linux port was in 2002 or so. I've used it extensively for the past 8 years. It is very stable, and many NAS companies have embedded it in their products. In particular, it works well even when the disk starts

Re: making file system block size bigger to improve hdfs performance ?

2011-10-10 Thread Brian Bockelman
I can provide another data point here: xfs works very well in modern Linuxes (in the 2.6.9 era, it had many memory management headaches, especially around the switch to 4k stacks), and its advantage is significant when you run file systems over 95% occupied. Brian On Oct 10, 2011, at 8:51 AM,

Re: making file system block size bigger to improve hdfs performance ?

2011-10-03 Thread Niels Basjes
Have you tried it to see what diffrence it makes? -- Met vriendelijke groet, Niels Basjes (Verstuurd vanaf mobiel ) Op 3 okt. 2011 07:06 schreef Jinsong Hu jinsong...@hotmail.com het volgende: Hi, There: I just thought an idea. When we format the disk , the block size is usually 1K to 4K. For

making file system block size bigger to improve hdfs performance ?

2011-10-02 Thread Jinsong Hu
Hi, There: I just thought an idea. When we format the disk , the block size is usually 1K to 4K. For hdfs, the block size is usually 64M. I wonder if we change the raw file system's block size to something significantly bigger, say, 1M or 8M, will that improve disk IO performance for hadoop's