Softupdates a mount option?

Ivan Voras ivoras at fer.hr
Thu May 27 05:32:01 PDT 2004


Bruce Evans wrote:

 > On Thu, 27 May 2004, Ivan Voras wrote:
 >
 >
 >>- I was creating a md drive with mdmfs, and it felt rather awkward to
 >>control softupdates via command line parameters (a sidequestion: does it
 >>make any sense enabling SU on a memory drive by default?). As it seems
 >>now, every such utility that handles (well, at least creates) a ffs
 >>filesystem must handle SU-controlling options as command line parameters.
 >
 >
 > It makes sense to never enable soft updates on a memory drive, since soft
 > updates uses extra CPU cycles to try to speed up i/o to real drives (and

Then maybe the default should be changed?

 From 'man mdmfs':
      By default, mdmfs creates a swap-based (MD_SWAP) disk with soft-updates
      enabled and mounts it on mount-point.


 > lately it doesn't seem to be very successful in doing the latter -- here
 > it is now about the same speed as normal mounts for copying /usr/src but
 > was 1.5 times faster a few years ago; async mounts are still 2.5 times
 > faster).

Yup, I noticed :(

*sigh*

-- 
Every sufficiently advanced magic is indistinguishable from technology
    - Arthur C Anticlarke



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