From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from localhost (localhost [127.0.0.1]) by olra.theworths.org (Postfix) with ESMTP id 0FEF6429E25 for ; Tue, 29 Nov 2011 13:04:01 -0800 (PST) X-Virus-Scanned: Debian amavisd-new at olra.theworths.org X-Spam-Flag: NO X-Spam-Score: -0.799 X-Spam-Level: X-Spam-Status: No, score=-0.799 tagged_above=-999 required=5 tests=[DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7] autolearn=disabled Received: from olra.theworths.org ([127.0.0.1]) by localhost (olra.theworths.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jhqC0Hd9ywYT for ; Tue, 29 Nov 2011 13:03:57 -0800 (PST) Received: from mail-bw0-f53.google.com (mail-bw0-f53.google.com [209.85.214.53]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by olra.theworths.org (Postfix) with ESMTPS id 2FF82431FB6 for ; Tue, 29 Nov 2011 13:03:57 -0800 (PST) Received: by bkaq10 with SMTP id q10so11571469bka.26 for ; Tue, 29 Nov 2011 13:03:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=from:to:subject:in-reply-to:references:user-agent:date:message-id :mime-version:content-type; bh=qSfejVeexNAlzdgPo5G7Lc2RvCkroozjd4BlgaQ8QLI=; b=RoG8PlyyfxVnkhcHx2Wvn0T8+WEPgdbC8J90bzb1IqugBBwongiNFoBukldnB+Pzav SbaXUG6+DuBydy4+d4+6eXcuMPl9hGiANfSubY/DNceeMae86afb28T8dw4YWQC/bOjp cgVNlX4YCf5Cr73Ibqgbu5aB0ce6o3z20tqG8= Received: by 10.205.123.16 with SMTP id gi16mr52029875bkc.41.1322600633987; Tue, 29 Nov 2011 13:03:53 -0800 (PST) Received: from localhost ([91.144.186.21]) by mx.google.com with ESMTPS id d2sm16204720bky.11.2011.11.29.13.03.50 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 29 Nov 2011 13:03:51 -0800 (PST) From: Dmitry Kurochkin To: Tomi Ollila , Tomi Ollila , notmuch@notmuchmail.org Subject: Re: [PATCH 1/3] test: add functions to count how much times notmuch was called In-Reply-To: References: <1322271878-32614-1-git-send-email-dmitry.kurochkin@gmail.com> <1322450895-32523-1-git-send-email-dmitry.kurochkin@gmail.com> <1322450895-32523-2-git-send-email-dmitry.kurochkin@gmail.com> <87hb1ovsz4.fsf@gmail.com> User-Agent: Notmuch/0.10+44~g067c44f (http://notmuchmail.org) Emacs/23.3.1 (x86_64-pc-linux-gnu) Date: Wed, 30 Nov 2011 01:03:27 +0400 Message-ID: <87aa7evdy8.fsf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-BeenThere: notmuch@notmuchmail.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: "Use and development of the notmuch mail system." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 29 Nov 2011 21:04:01 -0000 Hi Tomi. On Tue, 29 Nov 2011 14:58:00 +0200, Tomi Ollila wrote: > Hi Dmitry. > > On Tue, 29 Nov 2011 01:26:39 +0400, Dmitry Kurochkin wrote: > > Hi Tomi. > > > > On Mon, 28 Nov 2011 22:42:50 +0200, Tomi Ollila wrote: > > > On Mon, 28 Nov 2011 07:28:13 +0400, Dmitry Kurochkin wrote: > [ ... ] > > > > +# Creates a script that counts how much time it is executed and calls > > > > +# notmuch. $notmuch_counter_command is set to the path to the > > > > +# generated script. Use notmuch_counter_value() function to get the > > > > +# current counter value. > > > > +notmuch_counter_reset () { > > > > + notmuch_counter_command="$TMP_DIRECTORY/notmuch_counter" > > > > + if [ ! -x "$notmuch_counter_command" ]; then > > > > + notmuch_counter_state_path="$TMP_DIRECTORY/notmuch_counter.state" > > > > + cat >"$notmuch_counter_command" < > > > +#!/bin/sh > > > > + > > > > +count=\$(cat "$notmuch_counter_state_path") > > > > +echo -n \$(expr \$count + 1) > "$notmuch_counter_state_path" > > > > + > > > > +exec notmuch "\$@" > > > > +EOF > > > > + chmod +x "$notmuch_counter_command" || return > > > > + fi > > > > + > > > > + echo -n 0 > "$notmuch_counter_state_path" > > > > +} > > > > + > > > > +# Returns the current notmuch counter value. > > > > +notmuch_counter_value () { > > > > + if [ -r "$notmuch_counter_state_path" ]; then > > > > + count=$(cat "$notmuch_counter_state_path") > > > > + else > > > > + count=0 > > > > + fi > > > > + echo -n $count > > > > +} > > > > + > > > > > > Good work! It would be nice if the state file contained newline after > > > count number. > > > > I wonder why it is actually nice :) I do not have strong preference > > here. So a newline is added in v3. Also a newline is added to > > notmuch_counter_value() output for consistency. > > It is nice when I enter cat /path/to/notmuch_counter from command > line and shell prompt is not appended at the end of the file contents > (but on next line :) > > > > > > Also some optimizations could be done: > > > > > > > (Would be nice if you send a diff, or a human-friendly description of > > the changes.) > > Ok, I'll try to do this according to your wishes next time. > > > > cat >"$notmuch_counter_command" < > > #!/bin/sh > > > > > > read count < "$notmuch_counter_state_path" > > > > Nice. Fixed in the new patch version. > > > > > echo \$((count + 1)) > "$notmuch_counter_state_path" > > > > > > > I do not think this is really an optimization. And I find expr more > > clear than using $(()). I always have troubles remembering "random > > special char syntax" (yeah, not a Perl fan :)), prefer human friendly > > words. > > The (posix) shell command language defines 'Arithmetic Expansion' in > > http://pubs.opengroup.org/onlinepubs/007908799/xcu/chap2.html#tag_001_006_004 > > I.e. using format $(( expression )) makes shell doing the arithetic itself > instead of forking a process (or two!) to do so. > I though expr was a builtin. Now I agree that it is better to replace it with $(()), even though I still prefer the expr syntax. > Normally in this case it is not so big deal (and still it isn't, but...) > In this particular case the shell wrapper counting notmuch launches and > exec'ing it the wrapper could do this without fork(2)ing a single time > (i.e. keep the process count unchanged compared to execing notmuch > directly) > > Anyway, many opinions; as far as it works I'm fine with it :) > > Now that you feel relaxed, check the results of some further > experimentation ;) : > > excerpt from man strace: > > -ff If the -o filename option is in effect, each processes > trace is written to filename.pid where pid is the > numeric process id of each process. > > Executing rm -f forked.*; strace -ff -o forked bash -c 'echo $(( 5 + 5 ))' > > will output '10' and create just one 'forked.' file > > Executing rm -f forked.*; strace -ff -o forked bash -c 'echo $(expr 5 + 5)' > > output 10 as expected, but there is now *3* forked. files ! > > bash does not optmize; it forks subshell to execute $(...) and then > there just works as usual (forks subshell to execute builtin expr)) > > Executing rm -f forked.*; strace -ff -o forked bash -c 'echo $(exec expr 5 + 5)' > > (the added 'exec' takes off one fork -- just 2 forked. files appear). > > I did the same tests using dash, ksh & zsh on linux system, and every one > of these managed to optimize one fork out in the above 3 fork case. > Thanks for details. Regards, Dmitry > > Tomi