Re: Physical reads

From: K Gopalakrishnan <kaygopal_at_yahoo.com>
Date: Mon, 30 Dec 2002 02:09:01 -0800
Message-ID: <F001.00524099.20021230020901@fatcity.com>

Pradeep:

It is NOT number of read request to the I/O sub-system. It is number of blocks read from the disk. Note that the physical read is not necessarily a physical read. There are chances the block could be from Memory (file system buffer cache). This happens when you have quick IO and/or a large file system buffer cache.

So, in general 'physical reads' are the number of blcoks read in to the buffer cache from the disk !!

• pradeep_at_ibsplc.com wrote:
  >
  > Hi All in list,
  >
  > I have taken the report.txt using utlbstat and utlestat. Can I assume
  > that the physical reads value as number of physical I/Os to the disk
  > happened?
  

  ---

Have a nice day !!

---

Best Regards,
K Gopalakrishnan,
Bangalore, INDIA.

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Received on Mon Dec 30 2002 - 04:09:01 CST