I just hit a description of async IO in Oracle docs, it is very simply described there:
<quote> With synchronous I/O, when an I/O request is submitted to the operating system, the writing process blocks until the write is confirmed as complete. It can then continue processing. Asynchronous I/O allows a process to submit an I/O request but to then continue processing. It may then check on the result of the I/O at a later time. It is also possible to submit several I/O requests and then collect the status of those requests at a later time, thus allowing the operating system to parallelize any of those I/O operations, where possible. Parallel processing can reduce the overall time to complete an operation. Consider an extreme example: Imagine you want to write out four data blocks to four different files. With synchronous I/O you must submit block 1, wait, submit block 2, wait, submit block 3, wait, submit block 4, and wait. With asynchronous I/O, you can submit blocks 1, 2, 3, and 4 and then wait for all four blocks to complete. Because you gave the operating system all four I/O requests at once, it can act on all the requests in parallel. The total response time is only the duration of the longest I/O of the four, rather than the sum of all four I/O durations. </quote> Tanel. ----- Original Message ----- To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> Sent: Friday, September 19, 2003 5:24 PM > Ryan, > > You can have separate mount points from your server's perspective, but once you get into the NetApp it's just a pool of disk drives that are allocated as necessary by their WAFL (Write Anywhere File Layout) system. Therefore in reality you get zero benefit. > > Dick Goulet > Senior Oracle DBA > Oracle Certified 8i DBA > > -----Original Message----- > Sent: Thursday, September 18, 2003 10:10 PM > To: Multiple recipients of list ORACLE-L > > > Could you clarify something for me? Are you saying that if I have a variety > of 'mounts' on our netapp > > say > > /mnt1 > /mnt2 > > I would not benefit by putting my datafiles on seperate ones? I thought that > is where my I/O waits are coming from. Since we have all of our datafiles in > the same directory? > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Ryan > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Goulet, Dick > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Tanel Poder INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
