Re: [HACKERS] mmap vs read/write
Bruce Momjian <maillist@candle.pha.pa.us>
From: Bruce Momjian <maillist@candle.pha.pa.us>
To: count0@fsj.co.jp
Cc: hackers@postgreSQL.org
Date: 1998-05-15T22:16:58Z
Lists: pgsql-hackers
> This is unfair to mmap since mmap is called once > per page. Better to mmap large regions (many > pages at once), then use msync() to force > write any modified pages. Access purely in > memory mmap'd I/O is _many_ times faster than > read/write under Solaris or Linux later > than 2.1.99 (prior to 2.1.99, Linux had > slow mmap performance). This makes me feel better. Linux is killing BSD/OS in mapping tests. See my other posting. -- Bruce Momjian | 830 Blythe Avenue maillist@candle.pha.pa.us | Drexel Hill, Pennsylvania 19026 + If your life is a hard drive, | (610) 353-9879(w) + Christ can be your backup. | (610) 853-3000(h)