Does GNU emacs ever use shared libraries?

[John Robinson]

In article <PINKAS.89May14180259 at hobbit.intel.com>, pinkas at hobbit (Israel Pinkas ~) writes:
>SunOS 4.0 executables do not swap text pages by default (-z flag to ld).
>They are released from memory and marked as not present.  If needed again,
>they are loaded from the disk image.  If the original image is on an NFS
>mounted partition, every page fault results in an NFS access.  This hurts
>performance on large processes.  

This depends on your configuration.  If your swap device is remote via
ND or NFS, swapping a page results on two network accesses.  And ND is
more costly than NFS to boot.

>1) If the file server becomes unavailable (crashes, times out, etc.) the
>page fault can fail and the process can hang.  The network is flooded with
>NFS requests, which slows down everybody.

I don't think you can do much better than this with a diskless node.
To minimize your exposure, your executables and swap area should be
provided by the same server.  I don't know whether NFS or ND behaves
worse when the server croaks.

>2) If the image is deleted, everything goes haywire.

Whoa.  My understanding has always been that you can unlink a file,
but its inode stays around until every open FD on it is closed.  You
are implying that NFS breaks this behavior?  Seems to me that Unix
would have a hard time living with this change.

>(I didn't think that anybody would
>leave an Emacs process around for more than a week, but guess what?)

Sho nuff.  Do it all the time.
--
/jr
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C'mon big money!