From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: util-linux-owner@vger.kernel.org Received: from mail2.vodafone.ie ([213.233.128.44]:1739 "EHLO mail2.vodafone.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751290AbaG0MgI (ORCPT ); Sun, 27 Jul 2014 08:36:08 -0400 Message-ID: <53D4F231.9020906@draigBrady.com> Date: Sun, 27 Jul 2014 13:36:01 +0100 From: =?ISO-8859-1?Q?P=E1draig_Brady?= MIME-Version: 1.0 To: Andreas Henriksson CC: util-linux@vger.kernel.org Subject: Re: [PATCH] tests: allow non-inotify tailf to keep up References: <1406407441-4872-1-git-send-email-andreas@fatal.se> In-Reply-To: <1406407441-4872-1-git-send-email-andreas@fatal.se> Content-Type: text/plain; charset=ISO-8859-1 Sender: util-linux-owner@vger.kernel.org List-ID: On 07/26/2014 09:44 PM, Andreas Henriksson wrote: > When tailf is not using inotify, it seems to sleep for 0.25s between > checks. Just giving a 0.1s time window between update and removal of the > input file thus gives little chance for tailf to succeed. > Similar between startup and append to file, make sure initial > content is read before appending additional data by bumping the time. > > This should possibly be bumped much larger to make sure that > the tailf process actually gets a chance to run at all in the > given time window. Otherwise it might fail on really slow/overloaded > machines. > The drawback would then ofcourse be to increase the time it takes > to run the testsuite. > > Signed-off-by: Andreas Henriksson > --- > tests/ts/tailf/simple | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/tests/ts/tailf/simple b/tests/ts/tailf/simple > index 955844d..d0a1c5c 100755 > --- a/tests/ts/tailf/simple > +++ b/tests/ts/tailf/simple > @@ -27,9 +27,9 @@ echo {a..z} > $INPUT > > $TS_CMD_TAILF $INPUT > $TS_OUTPUT 2>&1 & > > -sleep 0.1 > +sleep 0.5 > echo {0..9} >> $INPUT > -sleep 0.1 > +sleep 0.5 > > rm -f $INPUT For such tests coreutils uses a helper function to apply a truncated exponential backoff, to run quickly in the common case, but also delay longer if necessary. See retry_delay_() at: http://git.sv.gnu.org/gitweb/?p=coreutils.git;a=blob;f=init.cfg;h=725ee121;hb=HEAD#l608 cheers, Pádraig.