Re: misc/54213 (Significant performance degradation of whatis(1) after src/usr.sbin/makemandb/whatis.c,-r1.6)

[Abhinav Upadhyay <er.abhinav.upadhyay%gmail.com@localhost>]

The following reply was made to PR misc/54213; it has been noted by GNATS.

From: Abhinav Upadhyay <er.abhinav.upadhyay%gmail.com@localhost>
To: NetBSD GNATS <gnats-bugs%netbsd.org@localhost>
Cc: Abhinav Upadhyay <abhinav%netbsd.org@localhost>, gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost, 
	Leonardo Taccari <leot%netbsd.org@localhost>
Subject: Re: misc/54213 (Significant performance degradation of whatis(1)
 after src/usr.sbin/makemandb/whatis.c,-r1.6)
Date: Sat, 18 May 2019 15:51:22 +0530

 On Sat, May 18, 2019 at 3:45 PM Leonardo Taccari <leot%netbsd.org@localhost> wrote:
 >
 > The following reply was made to PR misc/54213; it has been noted by GNATS.
 >
 > From: Leonardo Taccari <leot%NetBSD.org@localhost>
 > To: gnats-bugs%netbsd.org@localhost
 > Cc:
 > Subject: Re: misc/54213 (Significant performance degradation of whatis(1) after src/usr.sbin/makemandb/whatis.c,-r1.6)
 > Date: Sat, 18 May 2019 12:11:47 +0200
 >
 >  Hello Abhinav,
 >
 >  abhinav%NetBSD.org@localhost writes:
 >  > Synopsis: Significant performance degradation of whatis(1) after src/usr=
 >  .sbin/makemandb/whatis.c,-r1.6
 >  >
 >  > State-Changed-From-To: open->feedback
 >  > State-Changed-By: abhinav%NetBSD.org@localhost
 >  > State-Changed-When: Sat, 18 May 2019 07:58:39 +0000
 >  > State-Changed-Why:
 >  > Could you give the committed changes a try and see if it improves things=
 >  ?
 >
 >  Sure!
 >
 >  Redoing all the tests with whatis-1.5, whatis-1.7 and whatis-1.8.
 >  First I've prepared a man.db prior today commit using a
 >  `/tmp/man.conf.old', redoing the tests for whatis -r1.5 and -r1.7:
 >
 >   % time sh -c 'for i in $(seq 10); do { ./whatis-1.5 -C /tmp/man.conf.old =
 >  foo 2>/dev/null; } done'
 >   0.089u 0.234s 0:00.32 96.8%     50+1863k 0+0io 120pf+0w
 >
 >   % time sh -c 'for i in $(seq 10); do { ./whatis-1.7 -C /tmp/man.conf.old =
 >  foo 2>/dev/null; } done'
 >   28.916u 2.403s 0:31.31 100.0%   0+15k 0+0io 120pf+0w
 >
 >  ...then I've `cvs up' today changes, locally rebuilt makemandb and
 >  whatis and prepared a man.db using a `/tmp/man.conf', tests for
 >  whatis -r1.8:
 >
 >   % time sh -c 'for i in $(seq 10); do { ./whatis-1.8 -C /tmp/man.conf foo =
 >  2>/dev/null; } done'
 >   0.057u 0.269s 0:00.32 96.8%     50+1551k 0+0io 120pf+0w
 >
 >  So, yes, now the performance of -r1.8 are similar to the one of
 >  whatis.c -r1.5, thank you!
 >
 >  I have also checked that the resulting man.db sizes are comparable
 >  and they are both 42MB.
 >
 
 Great, thank you for verifying in detail :)
 >
 >  I think that whatis.c -r1.7 was accidentally reverted and case
 >  insensitive searchs no longer works, e.g.:
 >
 >   % ./whatis-1.5 -C /tmp/man.conf.old ApRoPoS
 >   ApRoPoS: not found
 >   % ./whatis-1.7 -C /tmp/man.conf.old ApRoPoS
 >   apropos(1) - search the complete content of all man pages
 >   % ./whatis-1.8 -C /tmp/man.conf ApRoPoS
 >   ApRoPoS: not found
 >
 >  Possible patch to reintroduce that:
 >
 >   <https://www.NetBSD.org/~leot/src-patches/whatis-nocase.patch>
 >
 >  If that's ok please let me know and I'll commit it (or feel free
 >  to commit it directly!).
 
 Yes, please commit it, thank you for noticing.
 >
 >  Apart that I think that also DBSCHEMA should be updated to document
 >  `name_desc' attribute of `mandb_links' table.
 
 Yes, good catch. If you get a chance do it or I will do when I get
 back to my machine.
 
 -
 Abhinav