Re: -CURRENT as of 14 Jan seems slow
On Wed, Jan 16, 2002 at 05:04:31PM +1100, Bruce Evans wrote: > On Tue, 15 Jan 2002, David Wolfskill wrote: > > > >Date: Tue, 15 Jan 2002 16:46:17 -0800 (PST) > > >From: John Baldwin <[EMAIL PROTECTED]> > > >Two questions: > > > > >1) Do you have WITNESS on in your kernel config? > > > > Yes, in both the build machine & the laptop -- since before I made a > > "local" hierarchy within my CVS repository (September 9, 2001). > > > > >2) If yes, have you tried building with a kernel without witness? > > > > No, not since I put it in to re-sync with GENERIC. I could try that, I > > suppose -- but as noted, I've had WITNESS in there for a while; something > > seems to have changed during that one 24-hr. period that affected things > > rather radically. And I thought it notable. :-} > > > > I gather no one else has noticed this? > > File locking seems to cause only the usual few percent of slowdown for > each round of major locking changes. I haven't completed benchmarking > the file locking pessimizations. I don't use WITNESS or INVARIANTS > for benchmarking of course. Maybe the file locking changes cause much > larger pessimizations when WITNESS is turned on than most locking > changes. I can see how they might: WITNESS seemed to slow down creation > and destruction of mutexes more than most mutex operations last time I > checked, and there is a descriptor for each file and each file descriptor. Note that additional locking with witness turned on can drastically affect performance. Chances are that Alfred's changes in combination with witness are what caused the slowdown. During certain stages of the lockmgr conversion to mutexes, I saw similar performance degradations (a factor of ~5-10, IIRC). Jason To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
RE: -CURRENT as of 14 Jan seems slow
On Tue, 15 Jan 2002, David Wolfskill wrote: > >Date: Tue, 15 Jan 2002 16:46:17 -0800 (PST) > >From: John Baldwin <[EMAIL PROTECTED]> > >Two questions: > > >1) Do you have WITNESS on in your kernel config? > > Yes, in both the build machine & the laptop -- since before I made a > "local" hierarchy within my CVS repository (September 9, 2001). > > >2) If yes, have you tried building with a kernel without witness? > > No, not since I put it in to re-sync with GENERIC. I could try that, I > suppose -- but as noted, I've had WITNESS in there for a while; something > seems to have changed during that one 24-hr. period that affected things > rather radically. And I thought it notable. :-} > > I gather no one else has noticed this? File locking seems to cause only the usual few percent of slowdown for each round of major locking changes. I haven't completed benchmarking the file locking pessimizations. I don't use WITNESS or INVARIANTS for benchmarking of course. Maybe the file locking changes cause much larger pessimizations when WITNESS is turned on than most locking changes. I can see how they might: WITNESS seemed to slow down creation and destruction of mutexes more than most mutex operations last time I checked, and there is a descriptor for each file and each file descriptor. Bruce To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
RE: -CURRENT as of 14 Jan seems slow
On 16-Jan-02 David Wolfskill wrote: >>Date: Tue, 15 Jan 2002 16:46:17 -0800 (PST) >>From: John Baldwin <[EMAIL PROTECTED]> > >>On 16-Jan-02 David Wolfskill wrote: >>> So... is this worth pursuing a bit more? > >>Two questions: > >>1) Do you have WITNESS on in your kernel config? > > Yes, in both the build machine & the laptop -- since before I made a > "local" hierarchy within my CVS repository (September 9, 2001). > >>2) If yes, have you tried building with a kernel without witness? > > No, not since I put it in to re-sync with GENERIC. I could try that, I > suppose -- but as noted, I've had WITNESS in there for a while; something > seems to have changed during that one 24-hr. period that affected things > rather radically. And I thought it notable. :-} > > I gather no one else has noticed this? Alfred added several more locks for file I/O stuff that could be the hit you are seeing. -- John Baldwin <[EMAIL PROTECTED]> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
Re: -CURRENT as of 14 Jan seems slow
On Tue, Jan 15, 2002 at 04:56:03PM -0800, David Wolfskill wrote: [...] > > I gather no one else has noticed this? Not here at least (timestamps are CET): note% ls -l /var/log/build/buildworld.log* -rw-r--r-- 1 root wheel 5728428 15 Jan 22:58 /var/log/build/buildworld.log -rw-r--r-- 1 root wheel 5727901 12 Jan 15:14 /var/log/build/buildworld.log.0 -rw-r--r-- 1 root wheel 5728013 11 Jan 04:35 /var/log/build/buildworld.log.1 -rw-r--r-- 1 root wheel 5701184 5 Jan 18:34 /var/log/build/buildworld.log.2 -rw-r--r-- 1 root wheel 5701184 5 Jan 18:34 /var/log/build/buildworld.log.3 note% egrep ' real.* user.* sys' /var/log/build/buildworld.log* /var/log/build/buildworld.log: 3860,96 real 2480,12 user 513,99 sys /var/log/build/buildworld.log.0: 4310,09 real 2948,09 user 560,00 sys /var/log/build/buildworld.log.1: 8044,91 real 2941,55 user 555,54 sys /var/log/build/buildworld.log.2: 4099,63 real 2935,31 user 562,73 sys /var/log/build/buildworld.log.3: 4099,63 real 2935,31 user 562,73 sys > david Cheers, Niels Chr. -- Niels Christian Bank-Pedersen, NCB1-RIPE. "Hey, are any of you guys out there actually *using* RFC 2549?" To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
RE: -CURRENT as of 14 Jan seems slow
>Date: Tue, 15 Jan 2002 16:46:17 -0800 (PST) >From: John Baldwin <[EMAIL PROTECTED]> >On 16-Jan-02 David Wolfskill wrote: >> So... is this worth pursuing a bit more? >Two questions: >1) Do you have WITNESS on in your kernel config? Yes, in both the build machine & the laptop -- since before I made a "local" hierarchy within my CVS repository (September 9, 2001). >2) If yes, have you tried building with a kernel without witness? No, not since I put it in to re-sync with GENERIC. I could try that, I suppose -- but as noted, I've had WITNESS in there for a while; something seems to have changed during that one 24-hr. period that affected things rather radically. And I thought it notable. :-} I gather no one else has noticed this? Cheers, david -- David H. Wolfskill [EMAIL PROTECTED] I believe it would be irresponsible (and thus, unethical) for me to advise, recommend, or support the use of any product that is or depends on any Microsoft product for any purpose other than personal amusement. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
RE: -CURRENT as of 14 Jan seems slow
On 16-Jan-02 David Wolfskill wrote: > So... is this worth pursuing a bit more? Two questions: 1) Do you have WITNESS on in your kernel config? 2) If yes, have you tried building with a kernel without witness? -- John Baldwin <[EMAIL PROTECTED]> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
