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From:shawn green Date:June 24 2013 5:24pm
Subject:Re: SHOW INNODB STATUS - FILE I/O - OS reads/writes/syncs?
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Hello Rafał,

On 6/24/2013 4:26 AM, Rafał Radecki wrote:
> As I can see the changes in these values are use by percona cacti
> monitoring templates to graph "InnoDB I/O".
> Can anyone answer the question finally? ;)
> 2013/6/21 Hartmut Holzgraefe <hartmut@stripped>
>> On 21.06.2013 13:59, Rafał Radecki wrote:
>>> Hi All.
>>> I've searched but with no luck... what do exactly these variables mean:
>>> 1343928 OS file reads, 1085452262 OS file writes, 19976022 OS fsyncs
>>> ?
>> these are the total number of reads/writes/fsyncs (number of system
>> calls actually?) since the server started (or maybe last FLUSH call?)
>> and not very meaningful by themselves without knowing the time span
>> it took to come up to those counter values.
>> The per second values on the following line are much more interesting.

I don't understand how Hartmut's answer was insufficient. The InnoDB 
engine must get data from the disk (reads), send data to the disk 
(writes), and occasionally tell the operating system that it must flush 
its buffers to disk to ensure durability (fsync).

Why are you so interested in these numbers?

Shawn Green
MySQL Principal Technical Support Engineer
Oracle USA, Inc. - Hardware and Software, Engineered to Work Together.
Office: Blountville, TN
SHOW INNODB STATUS - FILE I/O - OS reads/writes/syncs?Rafał Radecki21 Jun
  • Re: SHOW INNODB STATUS - FILE I/O - OS reads/writes/syncs?Hartmut Holzgraefe21 Jun
    • Re: SHOW INNODB STATUS - FILE I/O - OS reads/writes/syncs?Rafał Radecki24 Jun
      • Re: SHOW INNODB STATUS - FILE I/O - OS reads/writes/syncs?shawn green24 Jun
  • RE: SHOW INNODB STATUS - FILE I/O - OS reads/writes/syncs?Rick James25 Jun