• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: I/O Scheduler
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: I/O Scheduler


  • Subject: Re: I/O Scheduler
  • From: Ken Hornstein <email@hidden>
  • Date: Wed, 08 Aug 2012 09:07:49 -0400

>Maybe someone more knowledgeable can point out where in the VFS/UBC
>system the request combining happens - all I can say is I've certainly
>seen it in action from the requests it generates. There is also
>speculative read-ahead that causes I/O request sizes to grow
>exponentially when you read large files sequentially, which is
>presumably done in the same place. (you can easily observe this in
>action using dd and a filter scheme driver that logs requests)

I _think_ this happens in one of the cluster_* routines.  I'd have to
check to be sure.

--Ken
 _______________________________________________
Do not post admin requests to the list. They will be ignored.
Darwin-kernel mailing list      (email@hidden)
Help/Unsubscribe/Update your Subscription:

This email sent to email@hidden

References: 
 >Re: I/O Scheduler (From: Phil Jordan <email@hidden>)

  • Prev by Date: Re: I/O Scheduler
  • Next by Date: Re: Kernel crash on mac os x <= 10.6.8
  • Previous by thread: Re: I/O Scheduler
  • Next by thread: getpwnam("") && getgrnam("") returns an found entry but not NULL, is it a bug?
  • Index(es):
    • Date
    • Thread