Please add this bug to my sponsor requests:
BUG ID: 6920072
BUG Synopsis: ksh93 tail -f, with unconditional .25s sleep and line
parsing, about 37x slower than cat
2009/12/9 ????? ???????????? <olga.kryzhanovska at gmail.com>:
> This is a request for sponsors for fixing the following list of bugs:
>
> BUG ID: 6904557
> BUG Synopsis: wc no longer counts number of bytes correctly
>
> BUG ID: 6904575
> BUG Synopsis: cut -d with multibyte character no longer works
>
> BUG ID: 6904597
> BUG Synopsis: paste -d no longer works with multibyte characters
>
> BUG ID: 6904780
> BUG Synopsis: usr/bin/chksum changed output in snv_128
>
> BUG ID: 6904870
> BUG Synopsis: uniq -s does not skip multibyte characters correctly
>
> BUG ID: 6904878
> BUG Synopsis: join -t no longer works with multibyte char separator
>
>
> The same patch will fix the the P1 STOPPER bug:
> BUG ID: 6900314
> BUG Synopsis: (while true ; do true | true ; done) hang in ioctl() with
> SIGTTOU
>
>
> Name: Olga Kryzhanovska
> Opensolaris user name: fleyta
> SCA ID: #OS0402
> --
> , _ _ ,
> { \/`o;====- Olga Kryzhanovska -====;o`\/ }
> .----'-/`-/ olga.kryzhanovska at gmail.com \-`\-'----.
> `'-..-| / Solaris/BSD//C/C++ programmer \ |-..-'`
> /\/\ /\/\
> `--` `--`
>
---------- Forwarded message ----------
From: <[email protected]>
Date: Tue, Jan 26, 2010 at 8:21 AM
Subject: [ksh93-integration-discuss] CR 6920072 Updated, P3
utility/text ksh93 tail -f, with unconditional .25s sleep and line
parsing, about 37x slower than cat
To:
*Synopsis*: ksh93 tail -f, with unconditional .25s sleep and line
parsing, about 37x slower than cat
CR 6920072 changed on Jan 26 2010 by <User 1-5Q-1267>
=== Field ============ === New Value ============= === Old Value =============
See Also 6790507
====================== =========================== ===========================
*Change Request ID*: 6920072
*Synopsis*: ksh93 tail -f, with unconditional .25s sleep and line
parsing, about 37x slower than cat
Product: solaris
Category: utility
Subcategory: text
Type: Defect
Subtype:
Status: 1-Dispatched
Substatus:
Priority: 3-Medium
Introduced In Release:
Introduced In Build:
Responsible Engineer:
Keywords:
=== *Description* ============================================================
Running tail -f on a nightly.log during a build on an Opensolaris
snv_126 machine,
I noticed that the tail was running long after the build had
completed. The first
time I killed it; the second time I decided to let it run. *26
minutes* after the
build completed, it finally completed (the entire build had only taken
28 minutes).
Now, this was across an ssh connection from EGO02 to MPK17, but I took the same
log file and did several tests:
tail -f: 26:XX
nfs cp: 00:29
scp: 00:29
scp -C: 00:36
cat: 00:42
That's quite a difference.
Trussing the command, I see that it's ksh93, and that ksh is apparently reading
line-chunked things of approximately 8K, and writing line-chunked blocks to the
output, and unconditionally delaying .25s between each stat/read/write call.
That latter, in particular, seems to be the biggest problem, and seems
ill-advised;
if there's to be a delay, it seems like "stat, and if no change sleep and then
stat again" would be a lot more efficient.
Also, for -f, I don't see why there's any point in doing the
line-oriented calls;
original tail didn't, and I can't imagine it's a win.
*** (#1 of 1): 2010-01-26 04:51:29 GMT+00:00 <User 1-5Q-12546>
=== *Public Comments* ========================================================
=== *Workaround* =============================================================
=== *Additional Details* =====================================================
Targeted Release:
Commit To Fix In Build:
Fixed In Build:
Integrated In Build:
Verified In Build:
See Also: 6790507
Duplicate of:
Hooks:
Hook1:
Hook2:
Hook3:
Hook4:
Hook5:
Hook6:
Program Management:
Root Cause:
Fix Affects Documentation: No
Fix Affects Localization: No
=== *History* ================================================================
Date Submitted: 2010-01-26 04:51:29 GMT+00:00
Submitted By: <User 1-5Q-12546>
Status Changed Date Updated Updated By
=== *Service Request* ========================================================
Impact: Significant
Functionality: Secondary
Severity: 3
Product Name: solaris
Product Release: solaris_nevada
Product Build:
Operating System: snv_126
Hardware: generic
Submitted Date: 2010-01-26 04:51:30 GMT+00:00
=== *Multiple Release (MR) Cluster* - 0 ======================================
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ksh93-integration-discuss at opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/ksh93-integration-discuss
--
, _ _ ,
{ \/`o;====- Olga Kryzhanovska -====;o`\/ }
.----'-/`-/ olga.kryzhanovska at gmail.com \-`\-'----.
`'-..-| / Solaris/BSD//C/C++ programmer \ |-..-'`
/\/\ /\/\
`--` `--`
