Subject: new memory-miser tenex driver

From: Mark Crispin <[email-masked]>
Date: Sun, 28 Mar 1993 22:09:28 -0800 (PST)

The next version of the c-client distribution will come with tenex2, a new
memory-miser version of the tenex driver, as the default driver for the
mail.txt format.  It does not read the entire mailbox into memory, and thus
uses what can be significantly less memory than the original tenex driver.

For systems on which virtual memory/swap space is at a premium, this could
result in swap space savings and resultant performance improvement.  Users who
have particularly large mailboxes may wish to consider using the mail.txt
format once the tenex2 driver is installed in their mailer, since it may
result in significant real time speedups and a reduction of system overhead.

This is done at the possible cost of extra disk traffic and slower global free
text searches.  On a system with adequate memory for buffer cache, the
overhead compared to the original driver may be merely a matter of some extra
system call and context-switching overhead.

For the nonce, the original mail.txt format driver will still be available as
tenex.c/h, but the makefiles will only build the tenex2.c/h version.  If the
tenex2 driver turns out to be a winner, the original driver may be allowed to
succumb to software rot, so please let me know if the original driver is still
needed in your environment.