Re: Performance of -current vs -stable

2002-02-11 Thread Garance A Drosihn

At 12:10 AM -0500 2/6/02, Garance A Drosihn wrote:
One simple test I tried was that I have a copy of the freebsd cvs
repository in /usr/cvs/free, on it's own partition.  Each system
has it's own /usr/src, of course.  I cvsup'ed /usr/cvs/free, and
then did a
  time cvs status /dev/null
in each /usr/src, on each system.

The popular vote fingered the WITNESS option as the culprit for
the significant slowdown I noticed in -current.  I compiled a
kernel which did nothing but turn that off, and here is an
updated chart of my simple-minded benchmark:

 On current   On currentOn stable
 +witness NO witness   (no witness)
 --   --   --
real7m 43.392s   5m  9.443s   4m 53.100sin the /usr/src
user0m 11.692s   0m 11.223s   0m  4.203s   for current
sys 3m  4.601s   0m 17.353s   0m  2.248s

real6m 40.322s   1m 57.438s   2m 39.361sin the /usr/src
user0m 10.531s   0m  9.474s   0m  6.653s   for stable
sys 4m 28.863s   0m 12.527s   0m  9.480s

So, things are quite reasonable for my purposes if I turn off
the WITNESS kernel option, and leave all the other debugging
stuff active.

reminder: The above is obviously not a scientific benchmark!
It was just something adequate enough to show a rough idea
of the performance I was feeling.

Thanks for the pointers.  Now I'll try recompiling the rest of
the ports I have on my -stable system, and see if I can't keep
my office machine running in -current instead of -stable...

-- 
Garance Alistair Drosehn=   [EMAIL PROTECTED]
Senior Systems Programmer   or  [EMAIL PROTECTED]
Rensselaer Polytechnic Instituteor  [EMAIL PROTECTED]

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-11 Thread Wilko Bulte

On Thu, Feb 07, 2002 at 10:15:02AM +0100, Cejka Rudolf wrote:
 Garance A Drosihn wrote (2002/02/06):
  Anything else I should check?  I realize there's about a million
  differences between the two branches, and there might also be
  something about my machine's setup which is a major culprit here.
  I'm just looking for a basic idea of what other people have been
  seeing for performance when they run current.
 
 There is another common source of confusion: If anybody has IDE
 disks, write-caching is enabled by default in -stable, but disabled
 in -current.

I don't think that is true anymore. -stable has WC enabled as well.

-- 
|   / o / /_  _ [EMAIL PROTECTED]
|/|/ / / /(  (_)  Bulte Arnhem, the Netherlands

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-11 Thread Martin Faxér

On Thu, 7 Feb 2002 19:08:07 +0100
Wilko Bulte [EMAIL PROTECTED] wrote:

 On Thu, Feb 07, 2002 at 10:15:02AM +0100, Cejka Rudolf wrote:
   I'm just looking for a basic idea of what other people have been
   seeing for performance when they run current.
  
  There is another common source of confusion: If anybody has IDE
  disks, write-caching is enabled by default in -stable, but disabled
  in -current.
 
 I don't think that is true anymore. -stable has WC enabled as well.

-STABLE has it enabled indeed, but -CURRENT does not (afaik).
Read what he said. :-)

 
 -- 
 |   / o / /_  _   [EMAIL PROTECTED]
 |/|/ / / /(  (_)  Bulte   Arnhem, the Netherlands
 
 To Unsubscribe: send mail to [EMAIL PROTECTED]
 with unsubscribe freebsd-current in the body of the message
 

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-11 Thread Alexander Leidinger

On  6 Feb, Garance A Drosihn wrote:

 Anything else I should check?  I realize there's about a million
 differences between the two branches, and there might also be
 something about my machine's setup which is a major culprit here.
 I'm just looking for a basic idea of what other people have been
 seeing for performance when they run current.

# ll /etc/malloc.conf
lrwx--  1 root  wheel  2B Aug 18 21:47 /etc/malloc.conf@ - aj

Bye,
Alexander.

-- 
  Loose bits sink chips.

http://www.Leidinger.net   Alexander @ Leidinger.net
  GPG fingerprint = C518 BC70 E67F 143F BE91  3365 79E2 9C60 B006 3FE7


To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-11 Thread Georg-W Koltermann

At Wed, 06 Feb 2002 23:33:14 -0500 (EST),
John Baldwin wrote:
 
 [...]
 I guess.  Note that you can use a loader tunable 'debug.witness_watch' to turn
 witness off from the loader.  If it's set to 0 witness won't be used even if
 it's compiled into the kernel (just a general FYI, witness(4) documents this as
 well).

Nice feature, thanks for the hint.  I can't find it documented in
witness(4), however:

hunter# grep -i watch /usr/src/share/man/man4/witness.4
hunter# 

CVSup is from Feb 6.

--
Regards,
Georg.

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-11 Thread John Baldwin


On 07-Feb-02 Georg-W Koltermann wrote:
 At Wed, 06 Feb 2002 23:33:14 -0500 (EST),
 John Baldwin wrote:
 
 [...]
 I guess.  Note that you can use a loader tunable 'debug.witness_watch' to
 turn
 witness off from the loader.  If it's set to 0 witness won't be used even if
 it's compiled into the kernel (just a general FYI, witness(4) documents this
 as
 well).
 
 Nice feature, thanks for the hint.  I can't find it documented in
 witness(4), however:
 
 hunter# grep -i watch /usr/src/share/man/man4/witness.4
 hunter#   
 
 CVSup is from Feb 6.

Hmm, doh.  I document the other loader tunables and sysctls, just not
debug.witness_watch.  If someone with some mdoc fu and spare time wants to add
a para noting that debug.witness_watch can be set to 0 as a loader tunable to
turn off witness and that the read-only sysctl debug.witness_watch can be used
at runtime to see if witness is enabled or not.

 --
 Regards,
 Georg.

-- 

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

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-11 Thread BOUWSMA Beery


Serwoas!
%s wrote on %.3s, %lld Sep 1993

  Could it be due to the DDB, INVARIANTS  WITNESS options in the
  kernel?  If it is that's fine with me, I'm just wondering where
  that magnitude of a slowdown would be coming from.

 WITNESS can really hurt.  Quite possibly I should turn it off in GENERIC now (I

Hmmm, a few weeks ago I did some totally unscientific testing, noting
that -current was much slower than -stable, by playing an mp3 with an
optimized `mpg123' on a 75MHz pentium machine, where the difference was
far more obvious than on a faster machine.

I suspected that WITNESS and similar goodies might be a problem, and
even composed a lengthy message wondering about it, but what really
got me wondering was the fact that -stable had far less idle time than
the same hardware running NetBSD-current, so that I could do `useful'
work under NetBSD while playing an mp3 cleanly, but such was difficult
with FreeBSD-stable and impossible with -current.

However, I suspect that such a question is more on-topic in -hackers
or even -stable than here, but I'm wondering if I should extract any
useful info from the message I composed but never sent, and post my
kernel config and ask if there's anything obvious in there that would
explain why FreeBSD's mpg123 takes ~60% CPU and NetBSD's ~30% (vs the
~90+% usage by -current)...

Oh, I'll try rebuilding -current Real Soon^W^W later today, without
WITNESS, and compare, just to stay on-topic for this list.


thanks
barry bouwsma


To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-07 Thread Cejka Rudolf

Garance A Drosihn wrote (2002/02/06):
 Anything else I should check?  I realize there's about a million
 differences between the two branches, and there might also be
 something about my machine's setup which is a major culprit here.
 I'm just looking for a basic idea of what other people have been
 seeing for performance when they run current.

There is another common source of confusion: If anybody has IDE
disks, write-caching is enabled by default in -stable, but disabled
in -current.

-- 
Rudolf Cejka cejkar at fit.vutbr.cz http://www.fit.vutbr.cz/~cejkar
Brno University of Technology, Faculty of Information Technology
Bozetechova 2, 612 66  Brno, Czech Republic

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-07 Thread Georg-W Koltermann

At Wed, 06 Feb 2002 23:33:14 -0500 (EST),
John Baldwin wrote:
 
 [...]
 I guess.  Note that you can use a loader tunable 'debug.witness_watch' to turn
 witness off from the loader.  If it's set to 0 witness won't be used even if
 it's compiled into the kernel (just a general FYI, witness(4) documents this as
 well).

Nice feature, thanks for the hint.  I can't find it documented in
witness(4), however:

hunter# grep -i watch /usr/src/share/man/man4/witness.4
hunter# 

CVSup is from Feb 6.

--
Regards,
Georg.

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-07 Thread Wilko Bulte

On Thu, Feb 07, 2002 at 10:15:02AM +0100, Cejka Rudolf wrote:
 Garance A Drosihn wrote (2002/02/06):
  Anything else I should check?  I realize there's about a million
  differences between the two branches, and there might also be
  something about my machine's setup which is a major culprit here.
  I'm just looking for a basic idea of what other people have been
  seeing for performance when they run current.
 
 There is another common source of confusion: If anybody has IDE
 disks, write-caching is enabled by default in -stable, but disabled
 in -current.

I don't think that is true anymore. -stable has WC enabled as well.

-- 
|   / o / /_  _ [EMAIL PROTECTED]
|/|/ / / /(  (_)  Bulte Arnhem, the Netherlands

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-07 Thread Martin Faxér

On Thu, 7 Feb 2002 19:08:07 +0100
Wilko Bulte [EMAIL PROTECTED] wrote:

 On Thu, Feb 07, 2002 at 10:15:02AM +0100, Cejka Rudolf wrote:
   I'm just looking for a basic idea of what other people have been
   seeing for performance when they run current.
  
  There is another common source of confusion: If anybody has IDE
  disks, write-caching is enabled by default in -stable, but disabled
  in -current.
 
 I don't think that is true anymore. -stable has WC enabled as well.

-STABLE has it enabled indeed, but -CURRENT does not (afaik).
Read what he said. :-)

 
 -- 
 |   / o / /_  _   [EMAIL PROTECTED]
 |/|/ / / /(  (_)  Bulte   Arnhem, the Netherlands
 
 To Unsubscribe: send mail to [EMAIL PROTECTED]
 with unsubscribe freebsd-current in the body of the message
 

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-07 Thread Terry Lambert

Wilko Bulte wrote:
  There is another common source of confusion: If anybody has IDE
  disks, write-caching is enabled by default in -stable, but disabled
  in -current.
 
 I don't think that is true anymore. -stable has WC enabled as well.

Friends don't let friends cache writes

???

[1/2] 8-)... some IDE drives lie, when you tell them to flush
their caches.  [1] 8-(.

-- Terry

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-07 Thread John Baldwin


On 07-Feb-02 Georg-W Koltermann wrote:
 At Wed, 06 Feb 2002 23:33:14 -0500 (EST),
 John Baldwin wrote:
 
 [...]
 I guess.  Note that you can use a loader tunable 'debug.witness_watch' to
 turn
 witness off from the loader.  If it's set to 0 witness won't be used even if
 it's compiled into the kernel (just a general FYI, witness(4) documents this
 as
 well).
 
 Nice feature, thanks for the hint.  I can't find it documented in
 witness(4), however:
 
 hunter# grep -i watch /usr/src/share/man/man4/witness.4
 hunter#   
 
 CVSup is from Feb 6.

Hmm, doh.  I document the other loader tunables and sysctls, just not
debug.witness_watch.  If someone with some mdoc fu and spare time wants to add
a para noting that debug.witness_watch can be set to 0 as a loader tunable to
turn off witness and that the read-only sysctl debug.witness_watch can be used
at runtime to see if witness is enabled or not.

 --
 Regards,
 Georg.

-- 

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: Performance of -current vs -stable

2002-02-06 Thread BOUWSMA Beery


Serwoas!
%s wrote on %.3s, %lld Sep 1993

  Could it be due to the DDB, INVARIANTS  WITNESS options in the
  kernel?  If it is that's fine with me, I'm just wondering where
  that magnitude of a slowdown would be coming from.

 WITNESS can really hurt.  Quite possibly I should turn it off in GENERIC now (I

Hmmm, a few weeks ago I did some totally unscientific testing, noting
that -current was much slower than -stable, by playing an mp3 with an
optimized `mpg123' on a 75MHz pentium machine, where the difference was
far more obvious than on a faster machine.

I suspected that WITNESS and similar goodies might be a problem, and
even composed a lengthy message wondering about it, but what really
got me wondering was the fact that -stable had far less idle time than
the same hardware running NetBSD-current, so that I could do `useful'
work under NetBSD while playing an mp3 cleanly, but such was difficult
with FreeBSD-stable and impossible with -current.

However, I suspect that such a question is more on-topic in -hackers
or even -stable than here, but I'm wondering if I should extract any
useful info from the message I composed but never sent, and post my
kernel config and ask if there's anything obvious in there that would
explain why FreeBSD's mpg123 takes ~60% CPU and NetBSD's ~30% (vs the
~90+% usage by -current)...

Oh, I'll try rebuilding -current Real Soon^W^W later today, without
WITNESS, and compare, just to stay on-topic for this list.


thanks
barry bouwsma


To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread Alexander Leidinger

On  6 Feb, Garance A Drosihn wrote:

 Anything else I should check?  I realize there's about a million
 differences between the two branches, and there might also be
 something about my machine's setup which is a major culprit here.
 I'm just looking for a basic idea of what other people have been
 seeing for performance when they run current.

# ll /etc/malloc.conf
lrwx--  1 root  wheel  2B Aug 18 21:47 /etc/malloc.conf@ - aj

Bye,
Alexander.

-- 
  Loose bits sink chips.

http://www.Leidinger.net   Alexander @ Leidinger.net
  GPG fingerprint = C518 BC70 E67F 143F BE91  3365 79E2 9C60 B006 3FE7


To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread Steve Ames

On Wed, Feb 06, 2002 at 01:02:34AM -0500, John Baldwin wrote:
 
 On 06-Feb-02 Garance A Drosihn wrote:
  Could it be due to the DDB, INVARIANTS  WITNESS options in the
  kernel?  If it is that's fine with me, I'm just wondering where
  that magnitude of a slowdown would be coming from.
 
 WITNESS can really hurt.  Quite possibly I should turn it off in GENERIC 
 now (I wouldn't mind if someone else did that.)  Before major locking 
 changes people should still use it to look for bugs, but it isn't 
 very efficient I'm afraid. :(

Is 'AJ' still set in the malloc options? I seem to recall setting
/etc/malloc.conf once in CURRENT for performance reasons.

-Steve

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread David O'Brien

On Wed, Feb 06, 2002 at 01:02:34AM -0500, John Baldwin wrote:
 WITNESS can really hurt.  Quite possibly I should turn it off in
 GENERIC now (I wouldn't mind if someone else did that.)

I think it should stay.  Especially as we are not getting much usage in
-CURRENT.  If we turn it off by default, it should come back on 3 mo.
before 5.0-RELEASE for testing.  (and yes off for the actual release).

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread David O'Brien

On Wed, Feb 06, 2002 at 12:10:05AM -0500, Garance A Drosihn wrote:
  On current  On stable
  -- --
 real7m 43.392s 4m 53.100sin /usr/src for current
 user0m 11.692s 0m  4.203s
 sys 3m  4.601s 0m  2.248s
 
 real6m 40.322s 2m 39.361sin /usr/src for stable
 user0m 10.531s 0m  6.653s
 sys 4m 28.863s 0m  9.480s

...

 Could it be due to the DDB, INVARIANTS  WITNESS options in the


The order of magnitude increase in 'sys' time is the indication that
WITNESS is turned on.  Infact IIRC I once did a 'make -j8 buildworld' on
a dual Athlon system, and had sys  user.

-- 
-- David  ([EMAIL PROTECTED])

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread Emiel Kollof

On Wednesday 06 February 2002 06:10, Garance A Drosihn wrote:

[performance complaint snip]
 Could it be due to the DDB, INVARIANTS  WITNESS options in the
 kernel?  If it is that's fine with me, I'm just wondering where
 that magnitude of a slowdown would be coming from.

I would think so (iow, those are the biggest culprits). There are also some 
other issues (wrt locking and probably some other stuff) but they are 
bearable. I am running a PII 400 with 64 MB with CURRENT, it mighn't be the 
fastest now, but at least it works. I have been stresstesting the damn thing
(as in, run lots of (relatively) useless services on there like icecast, and 
more ;-) and it is still holding. So far so good. The performance is low? 
Didn't notice that (but do keep in mind I'm happy with very little :-). It's 
not even buckling under a constant load avg of between 1.something and 
3.something and 200+ procs running at all times... No dataloss yet. Very good.

[snip] 

 I'm just looking for a basic idea of what other people have been
 seeing for performance when they run current.

My performance is okay from what I expect of it. Of course I have DDB, 
INVARIANTS and WITNESS options on (to provide better info for the developers 
when it crashes for some unexplainable reason). If you are planning to do 
'production' (mind the quotes) stuff with CURRENT, I suggest you could strip 
those. But beware, you are on the bleeding edge here :-)

Cheers,
Emiel
-- 
The problem with the gene pool is that there is no lifeguard.

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread Garance A Drosihn

At 9:13 AM -0800 2/6/02, David O'Brien wrote:
On Wed, Feb 06, 2002 at 01:02:34AM -0500, John Baldwin wrote:
  WITNESS can really hurt.  Quite possibly I should turn it off in
  GENERIC now (I wouldn't mind if someone else did that.)

I think it should stay.  Especially as we are not getting much usage in
-CURRENT.  If we turn it off by default, it should come back on 3 mo.
before 5.0-RELEASE for testing.  (and yes off for the actual release).

I was thinking that maybe it should stay in the GENERIC kernel, along
with some comment that indicates how much of a performance hit will
be seen if it's on.  This is desirable for in-depth debugging, but
it does mean that system calls will take three times longer than if
the option is off.  It's good to have the extra checking, but we
don't want to scare people away from running current simply because
they think it will take three times longer to get anything done on
current.

(or maybe even comment the option out, but do leave the line there
along with the statement that we'd appreciate it if people would
run with this option on, even though it will cause a noticeable
slowdown.).

I do think it's important that we (developers) spend more time on
current, but I think the way I'll do it is to compile two kernels,
one with the WITNESS and one without it.  For much of what I do I
can absorb the extra overhead of WITNESS code, but a three-hour
buildworld will throw my entire buildworld schedule off, and I
just won't be able to rebuild the system as often.

-- 
Garance Alistair Drosehn=   [EMAIL PROTECTED]
Senior Systems Programmer   or  [EMAIL PROTECTED]
Rensselaer Polytechnic Instituteor  [EMAIL PROTECTED]

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread Garance A Drosihn

At 12:10 AM -0500 2/6/02, Garance A Drosihn wrote:
One simple test I tried was that I have a copy of the freebsd cvs
repository in /usr/cvs/free, on it's own partition.  Each system
has it's own /usr/src, of course.  I cvsup'ed /usr/cvs/free, and
then did a
  time cvs status /dev/null
in each /usr/src, on each system.

The popular vote fingered the WITNESS option as the culprit for
the significant slowdown I noticed in -current.  I compiled a
kernel which did nothing but turn that off, and here is an
updated chart of my simple-minded benchmark:

 On current   On currentOn stable
 +witness NO witness   (no witness)
 --   --   --
real7m 43.392s   5m  9.443s   4m 53.100sin the /usr/src
user0m 11.692s   0m 11.223s   0m  4.203s   for current
sys 3m  4.601s   0m 17.353s   0m  2.248s

real6m 40.322s   1m 57.438s   2m 39.361sin the /usr/src
user0m 10.531s   0m  9.474s   0m  6.653s   for stable
sys 4m 28.863s   0m 12.527s   0m  9.480s

So, things are quite reasonable for my purposes if I turn off
the WITNESS kernel option, and leave all the other debugging
stuff active.

reminder: The above is obviously not a scientific benchmark!
It was just something adequate enough to show a rough idea
of the performance I was feeling.

Thanks for the pointers.  Now I'll try recompiling the rest of
the ports I have on my -stable system, and see if I can't keep
my office machine running in -current instead of -stable...

-- 
Garance Alistair Drosehn=   [EMAIL PROTECTED]
Senior Systems Programmer   or  [EMAIL PROTECTED]
Rensselaer Polytechnic Instituteor  [EMAIL PROTECTED]

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-06 Thread John Baldwin


On 06-Feb-02 David O'Brien wrote:
 On Wed, Feb 06, 2002 at 01:02:34AM -0500, John Baldwin wrote:
 WITNESS can really hurt.  Quite possibly I should turn it off in
 GENERIC now (I wouldn't mind if someone else did that.)
 
 I think it should stay.  Especially as we are not getting much usage in
 -CURRENT.  If we turn it off by default, it should come back on 3 mo.
 before 5.0-RELEASE for testing.  (and yes off for the actual release).

I guess.  Note that you can use a loader tunable 'debug.witness_watch' to turn
witness off from the loader.  If it's set to 0 witness won't be used even if
it's compiled into the kernel (just a general FYI, witness(4) documents this as
well).

-- 

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: Performance of -current vs -stable

2002-02-05 Thread M. Warner Losh

In message: p05101401b88638b62611@[128.113.24.47]
Garance A Drosihn [EMAIL PROTECTED] writes:
: Could it be due to the DDB, INVARIANTS  WITNESS options in the
: kernel?  If it is that's fine with me, I'm just wondering where
: that magnitude of a slowdown would be coming from.

No way for DDB, Maybe for Invariants, almost certainly for witness.
WITNESS is slow and tends to exagerate lock contention stalls (or so
it seems).

Warner

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



Re: Performance of -current vs -stable

2002-02-05 Thread k Macy

I asked BDE about the same thing off-list:
Yes, the debug options (INVARIANTS and WITNESS,
especially the latter)
slow down the kernel by a factor of 10 or so.  Only
progams that don't
make many syscalls run reasonably fast.  I only turn
on these options
for debugging (not often).  Without them, syscalls
should be an average
of only (sigh) about 10% slower in -current.

--- M. Warner Losh [EMAIL PROTECTED] wrote:
 In message: p05101401b88638b62611@[128.113.24.47]
 Garance A Drosihn [EMAIL PROTECTED]
 writes:
 : Could it be due to the DDB, INVARIANTS  WITNESS
 options in the
 : kernel?  If it is that's fine with me, I'm just
 wondering where
 : that magnitude of a slowdown would be coming from.
 
 No way for DDB, Maybe for Invariants, almost
 certainly for witness.
 WITNESS is slow and tends to exagerate lock
 contention stalls (or so
 it seems).
 
 Warner
 
 To Unsubscribe: send mail to [EMAIL PROTECTED]
 with unsubscribe freebsd-current in the body of
 the message
 
 


__
Do You Yahoo!?
Send FREE Valentine eCards with Yahoo! Greetings!
http://greetings.yahoo.com

To Unsubscribe: send mail to [EMAIL PROTECTED]
with unsubscribe freebsd-current in the body of the message



RE: Performance of -current vs -stable

2002-02-05 Thread John Baldwin


On 06-Feb-02 Garance A Drosihn wrote:
 Could it be due to the DDB, INVARIANTS  WITNESS options in the
 kernel?  If it is that's fine with me, I'm just wondering where
 that magnitude of a slowdown would be coming from.

WITNESS can really hurt.  Quite possibly I should turn it off in GENERIC now (I
wouldn't mind if someone else did that.)  Before major locking changes people
should still use it to look for bugs, but it isn't very efficient I'm afraid. :(

-- 

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