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Full Discussion: Slow copy (cp) performance when overwriting files
Special Forums Hardware Filesystems, Disks and Memory Slow copy (cp) performance when overwriting files Post 302831993 by jim mcnamara on Friday 12th of July 2013 11:09:22 AM
Old 07-12-2013
Also consider that
IF:
directory has large numbers of entries - >40K (varies with filesystem type)

Cure: make a directory tree, with each subdirectory having way smaller numbers of files.

Overly full disks can result in fragmented files which trashes update (cp overlay) performance of larger files.

So: You can experience lots of delay finding and overwriting files.

Another cause is poor inode caching. This is OS specific, I cannot comment specifically. But when you try to find a file in a directory, the kernel checks the inode cache first. If it finds the file in the cache it can open the file right away without having to scan thru a huge directory. inode caching also impacts the efficiency of PATH searching.
 

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LEARN ABOUT OSF1

rmm

rmm(1)							      General Commands Manual							    rmm(1)

NAME

       rmm - remove messages (only available within the message handling system, mh)

SYNOPSIS

       rmm [+folder] [msgs] [-help]

OPTIONS

       Prints a list of the valid options to this command.

       The default settings for this command are:

       +folder defaults to the current folder msgs defaults to the current message

DESCRIPTION

       The rmm command deletes the current message from the current folder.

       You can specify messages and folders other than the current ones by using the +folder and msgs arguments.

       The current message is not changed by rmm, so a next will advance to the next message in the folder as expected.

       If you have defined a component rmmproc: in your file, then instead of simply renaming the message file, rmm will call the named program to
       delete the file.

       The rmm command removes messages by renaming the message files with a preceding comma. Many sites consider files that start with a comma to
       be a temporary backup, and arrange for cron(8) to remove such files once a day.

PROFILE COMPONENTS

       Path: To determine your Mail directory

       rmmproc: Program to delete the message

FILES

       The user profile.

SEE ALSO

       rmf(1)

																	    rmm(1)
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