Re: VxFS block size with db block size =16k

"Marco Vannini" <m.vannini_at_tinCANCELLA.it> wrote in message news:<pwW5b.34945$w8.4965_at_news.edisontel.com>...
> Hi, we 're managing a 8.1.7.4 VLDB (about 1TB) for DSS on SUN 3800, T3
> storage, Solaris 8, UFS with forcedirectio options for datafiles and raw
> redo. Even if we're quite satisfied with the performance, we've purchased
> Veritas Filesistem (not quick i/o), and considering to pass from UFS to
> VxFS, maintaining the direct access (micache=direct convosync=direct).
> Since the db_block_size=16k, is it better to make filesystems with 16k
> block size or maintain the 8k of the actual UFS ?

Hi, Marco,

FYI, Bert Scalzo's test on Linux (published in Linux Journal) shows that 8k db_block_size gives faster data load than 4k, the default filesystem block size. My friend chao_ping's test on RH Linux AS using 9i tablespace multiple blocksize (un-published) shows that 16k has slight performance advantage over 4k in insert and significant advantage in full table scan, with db_block_size set to 8k. I would appreciate it if you could do a test and post the result here.

Yong Huang Received on Tue Sep 09 2003 - 21:11:05 CDT