[PATCH] bio.c: reduce verbosity at boot

[PATCH] bio.c: reduce verbosity at boot

[Matthew Wilcox]

Linux is really far too verbose at boot time.  I don't think these messages
add anything to either the end user experience or debug ability.

Index: fs/bio.c
===================================================================
RCS file: /var/cvs/linux-2.6/fs/bio.c,v
retrieving revision 1.2
diff -u -p -r1.2 bio.c
--- fs/bio.c	29 Jul 2003 17:25:49 -0000	1.2
+++ fs/bio.c	21 Aug 2003 14:58:40 -0000
@@ -793,10 +793,6 @@ static void __init biovec_init_pools(voi
 					mempool_free_slab, bp->slab);
 		if (!bp->pool)
 			panic("biovec: can't init mempool\n");
-
-		printk("biovec pool[%d]: %3d bvecs: %3d entries (%d bytes)\n",
-						i, bp->nr_vecs, pool_entries,
-						size);
 	}
 }
 
@@ -809,8 +805,6 @@ static int __init init_bio(void)
 	bio_pool = mempool_create(BIO_POOL_SIZE, mempool_alloc_slab, mempool_free_slab, bio_slab);
 	if (!bio_pool)
 		panic("bio: can't create mempool\n");
-
-	printk("BIO: pool of %d setup, %ZuKb (%Zd bytes/bio)\n", BIO_POOL_SIZE, BIO_POOL_SIZE * sizeof(struct bio) >> 10, sizeof(struct bio));
 
 	biovec_init_pools();
 

-- 
"It's not Hollywood.  War is real, war is primarily not about defeat or
victory, it is about death.  I've seen thousands and thousands of dead bodies.
Do you think I want to have an academic debate on this subject?" -- Robert Fisk

Re: [PATCH] bio.c: reduce verbosity at boot

[Jeff Garzik]

Matthew Wilcox wrote:
> Linux is really far too verbose at boot time.  I don't think these messages
> add anything to either the end user experience or debug ability.
> 
> Index: fs/bio.c
> ===================================================================
> RCS file: /var/cvs/linux-2.6/fs/bio.c,v
> retrieving revision 1.2
> diff -u -p -r1.2 bio.c
> --- fs/bio.c	29 Jul 2003 17:25:49 -0000	1.2
> +++ fs/bio.c	21 Aug 2003 14:58:40 -0000
> @@ -793,10 +793,6 @@ static void __init biovec_init_pools(voi
>  					mempool_free_slab, bp->slab);
>  		if (!bp->pool)
>  			panic("biovec: can't init mempool\n");
> -
> -		printk("biovec pool[%d]: %3d bvecs: %3d entries (%d bytes)\n",
> -						i, bp->nr_vecs, pool_entries,
> -						size);


Although I agree with your "too verbose" sentiment above, I think the 
removing the messages outright might not serve the best interests the 
developer.  Since even KERN_DEBUG still spams dmesg, in these situations 
I usually change these type of messages to be conditionally printed iff 
a debug macro is enabled.

As a tangent, the huge x86 IO-APIC verbosity really bugs me, too, and 
often is the direct cause of useful early printk messages being lost 
before boot is even complete.

	Jeff

Re: [PATCH] bio.c: reduce verbosity at boot

[Lou Langholtz]

Jeff Garzik wrote:

> Matthew Wilcox wrote:
>
>> Linux is really far too verbose at boot time.  I don't think these 
>> messages
>> add anything to either the end user experience or debug ability.
>>
>> Index: fs/bio.c
>> ===================================================================
>> RCS file: /var/cvs/linux-2.6/fs/bio.c,v
>> retrieving revision 1.2
>> diff -u -p -r1.2 bio.c
>> --- fs/bio.c    29 Jul 2003 17:25:49 -0000    1.2
>> +++ fs/bio.c    21 Aug 2003 14:58:40 -0000
>> @@ -793,10 +793,6 @@ static void __init biovec_init_pools(voi
>>                      mempool_free_slab, bp->slab);
>>          if (!bp->pool)
>>              panic("biovec: can't init mempool\n");
>> -
>> -        printk("biovec pool[%d]: %3d bvecs: %3d entries (%d bytes)\n",
>> -                        i, bp->nr_vecs, pool_entries,
>> -                        size);
>
>
> . . . removing the messages outright might not serve the best 
> interests the developer.  Since even KERN_DEBUG still spams dmesg, in 
> these situations I usually change these type of messages to be 
> conditionally printed iff a debug macro is enabled.

How about using KERN_DEBUG and augmenting the dmesg store so that the 
level that is saved is configurable? Even compile time configurable 
seems reasonable to start. But axeing out even the possibility of boot 
time info seems bad to me.

Re: [PATCH] bio.c: reduce verbosity at boot

[Matthew Wilcox]

On Thu, Aug 21, 2003 at 10:51:27AM -0600, Lou Langholtz wrote:
> Jeff Garzik wrote:
> >. . . removing the messages outright might not serve the best 
> >interests the developer.  Since even KERN_DEBUG still spams dmesg, in 
> >these situations I usually change these type of messages to be 
> >conditionally printed iff a debug macro is enabled.
> 
> How about using KERN_DEBUG and augmenting the dmesg store so that the 
> level that is saved is configurable? Even compile time configurable 
> seems reasonable to start. But axeing out even the possibility of boot 
> time info seems bad to me.

But why is it interesting to have this information at boot time?  As a
user, I certainly don't care.  As a developer, I don't find it interesting
information.  Maybe the maintainer of this particular piece of code finds
it useful (Do you, Jens?), but does it need to be reported at boot time?

Perhaps it would be more useful to add some kind of reporting to
mm/mempool.c along the same lines as /proc/slabinfo so we can get the
dynamic information about pools at runtime rather than knowing their
initial state at boot time.

-- 
"It's not Hollywood.  War is real, war is primarily not about defeat or
victory, it is about death.  I've seen thousands and thousands of dead bodies.
Do you think I want to have an academic debate on this subject?" -- Robert Fisk

Re: [PATCH] bio.c: reduce verbosity at boot

[Linus Torvalds]

On Thu, 21 Aug 2003, Matthew Wilcox wrote:
> 
> But why is it interesting to have this information at boot time?  As a
> user, I certainly don't care.  As a developer, I don't find it interesting
> information.

I do agree. The message may have been useful when the code was young and 
people wanted to see that it got executed correctly at all, but there 
doesn't seem to be a lot of point to it any more.

But hey, I'll leave it to the maintainer..

		Linus

Re: [PATCH] bio.c: reduce verbosity at boot

[David Lang]

On Thu, 21 Aug 2003, Linus Torvalds wrote:

> On Thu, 21 Aug 2003, Matthew Wilcox wrote:
> >
> > But why is it interesting to have this information at boot time?  As a
> > user, I certainly don't care.  As a developer, I don't find it interesting
> > information.
>
> I do agree. The message may have been useful when the code was young and
> people wanted to see that it got executed correctly at all, but there
> doesn't seem to be a lot of point to it any more.
>
> But hey, I'll leave it to the maintainer..
>
> 		Linus

as a user I find a minimal set of messages (loading driver, hardware
found) handy for identifying what hardware is actually in old machines I
am given.

that said there is a lot of distance between that and the current
situation where you print out 3-4 screens worth of info for a single
driver.

David Lang

Re: [PATCH] bio.c: reduce verbosity at boot

[Jens Axboe]

On Thu, Aug 21 2003, Linus Torvalds wrote:
> 
> On Thu, 21 Aug 2003, Matthew Wilcox wrote:
> > 
> > But why is it interesting to have this information at boot time?  As a
> > user, I certainly don't care.  As a developer, I don't find it interesting
> > information.
> 
> I do agree. The message may have been useful when the code was young and 
> people wanted to see that it got executed correctly at all, but there 
> doesn't seem to be a lot of point to it any more.
> 
> But hey, I'll leave it to the maintainer..

Willy's patch is fine with me as well. Purpose of the messages is long
gone.

-- 
Jens Axboe

Re: [PATCH] bio.c: reduce verbosity at boot

[Diego Calleja García]

El Thu, 21 Aug 2003 10:51:27 -0600 Lou Langholtz <ldl@aros.net> escribió:

> How about using KERN_DEBUG and augmenting the dmesg store so that the 
> level that is saved is configurable? Even compile time configurable 
> seems reasonable to start. But axeing out even the possibility of boot 
> time info seems bad to me.

Like this?

(14) Kernel log buffer size (16 => 64KB, 17 => 128KB)  

Available at least in 2.6.0-test3 under "General setup"

Re: [PATCH] bio.c: reduce verbosity at boot

[Lou Langholtz]

Diego Calleja García wrote:

>El Thu, 21 Aug 2003 10:51:27 -0600 Lou Langholtz <ldl@aros.net> escribió:
>  
>
>>How about using KERN_DEBUG and augmenting the dmesg store so that the 
>>level that is saved is configurable? Even compile time configurable 
>>seems reasonable to start. But axeing out even the possibility of boot 
>>time info seems bad to me.
>>    
>>
>Like this?
>(14) Kernel log buffer size (16 => 64KB, 17 => 128KB)  
>Available at least in 2.6.0-test3 under "General setup"
>  
>
Yes, except I was thinking for loglevel rather than size. Is a loglevel 
option - as in only save printk's above level X in dmesg - already 
available? I've seen other emails fly by on the printk system before so 
this could well already be available. I haven't checked but was assuming 
from the emails I'd seen so far that this didn't exist and was merely 
suggesting this thinking it'd be an easy addition to the dmesg store.