From: yong huang Date: Fri, 29 Dec 2000 08:06:10 -0800 (PST) Subject: Re: I/O buffer cache On UNIX and Linux, you can run perl -e '@a = stat("."); print $a[11]' which is just a convenient way to get the value of the 12th element of the array returned by stat(2). On System V, this 12th element is a suggested or optimal value of I/O size, meaning there could be a smaller I/O chunk size called fragment. I tested the above Perl one liner on a number of UNIX systems I have access to, including OpenBSD, Solaris, Linux, Tru64 and OSF/1. They're all 8192 except on Linux, which is 4k. These're just the common block size system admins configure. Could vary. In Windows, direct I/O (bypassing file system I/O) is used. The argument about I/O buffer size loses its weight and probably becomes irrelevant. Yong Huang yong321 AT yahoo.com you wrote: hi, as my name suggests i am a novice. i was reading ORACLE 8i DBA handbook by Kevin Loney and Marlene Theriault. in the 5th chapter the author speaks of how I/O buffer cache affect the sizing. My question is how do i findout what is my operating system's I/O buffer cache. I work on Oracle 8.1.7 on Windows NT 4.0 with SP5. 128 MB RAM and Redhat Linux 7.0 128MB RAM