Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!van-bc!mplex!grassys!ror
From: ror@grassys.bc.ca (Richard O'Rourke)
Newsgroups: comp.mail.elm
Subject: Re: Faster reading of mailboxes with indexing
Keywords: elm mailbox fast index feature
Message-ID: <155@grassys.bc.ca>
Date: 1 Mar 90 07:49:03 GMT
References: <1887@uniol.UUCP> <1990Feb28.230830.9818@DSI.COM>
Distribution: comp
Organization: Grass Root Systems, Burnaby, B.C., Canada
Lines: 31

In article <1990Feb28.230830.9818@DSI.COM>, syd@DSI.COM (Syd Weinstein) writes:
> henseler@uniol.UUCP (Herwig Henseler) writes:
# 
# >When Un*x-mailers read a mailbox, they have to scan the whole file for
# >"From_"-lines to detect the top of the messages. So does elm. I can hardly
# >imagine a more uneffective way of achieving this aim! The mailbox format
# >is old enough to overcome an improvement...
# 
# >Idea: Why not index this positions in a second file, so that only this
# >      file (with seek-positions for every "From_"-line together with the
# >      "From:"-entry, the "Subject:"-line and the total amount of lines)
# >      has to be scanned to build the internal tables for elm. This will be
# >      _much_ faster !
# This was discusses a while back in the development group.  Two proposals
# were considered, one imbed the index in the file itself as a fake pseudo
# message, the second was to use a seperate file, with the sub ideas
# of one file per user or one file per mail file.
# 

If you're going to go through this much trouble, I respectfully
recommend a reading of the applicable X.400 docs on message data
base handling.  I'm not suggesting you spend your next year
implementing X.400.  I am suggesting that if you are going to take
the step of using 'mangled' message files or some sort of keyed
or database message system, that a perusal of applicable standards
is in order.  It would be a step in the right direction.

# =====================================================================
# Sydney S. Weinstein, CDP, CCP                   Elm Coordinator
# Datacomp Systems, Inc.				Voice: (215) 947-9900
# syd@DSI.COM or {bpa,vu-vlsi}!dsinc!syd	        FAX:   (215) 938-0235