Re: Relative performance of swap-backed MFS vs. regular UFS?

From: Dag-Erling Smørgrav (des_at_des.no)
Date: 10/23/04

  • Next message: Ryan Sommers: "Re: bootable install CD - relocate to subdir" 
    To: Clifton Royston <cliftonr@lava.net>
Date: Sat, 23 Oct 2004 16:10:41 +0200

    Clifton Royston <cliftonr@lava.net> writes:
    > For a large temporary file system which must hold short-lived files,
    > mostly small but occasionally several very large ones (e.g. 100MB+), is
    > it better for performance and stability if this file system:
    >
    > 1) resides on a swap-backed MFS and trusts the OS to swap out
    > low-priority blocks if needed under RAM pressure, or
    >
    > 2) on a regular UFS and trusts the OS to buffer as many blocks as
    > possible into RAM when RAM is free?

    the former, provided you have enough RAM. A swap-backed MFS will only
    swap out when it has to, while a UFS will always write out changes
    after a while.

    > I temporarily enlarged it to 256MB which is working, but as I worked
    > out the worst case scenario, I realized it really would need to be
    > nearly 1GB to handle multiple zip-bombs each hitting the 100MB size
    > limit. This makes me wonder if it's wise to specify a 1GB MFS on a
    > system with only 1GB RAM, or wiser to just revert to a regular file
    > system?

    RAM is cheap. Toss in a couple extra gig and set up a 2 GB MFS.

    DES 

    -- 
Dag-Erling Smørgrav - des@des.no
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  • Next message: Ryan Sommers: "Re: bootable install CD - relocate to subdir"

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