Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-11 Thread Bryn M. Reeves
On Wed, Feb 11, 2015 at 06:30:27AM +0800, Greg KH wrote: > On Tue, Feb 10, 2015 at 02:27:20PM +, Bryn M. Reeves wrote: > > On Sat, Feb 07, 2015 at 12:07:43PM +0800, Greg KH wrote: > > > > $ cat /sys/fs/selinux/avc/cache_stats > > lookups hits misses allocations reclaims frees > > 18938916 189

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-10 Thread Greg KH
On Tue, Feb 10, 2015 at 02:27:20PM +, Bryn M. Reeves wrote: > On Sat, Feb 07, 2015 at 12:07:43PM +0800, Greg KH wrote: > > $ cat /sys/fs/selinux/avc/cache_stats > lookups hits misses allocations reclaims frees > 18938916 18921707 17209 17209 17328 22215 > 38164283 38146514 17769 17769 16800 1

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-10 Thread Bryn M. Reeves
On Sat, Feb 07, 2015 at 12:07:43PM +0800, Greg KH wrote: > On Fri, Feb 06, 2015 at 03:41:58PM +, Bryn M. Reeves wrote: > > I can't speak for Shane but wouldn't spend too much time looking at the > > current v2 patch: it's the result of a pretty ugly compromise suggested > > on linux-scsi. > >

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-08 Thread James Bottomley
On Sun, 2015-02-08 at 10:45 +0800, Greg KH wrote: > On Sat, Feb 07, 2015 at 09:27:05PM -0500, Laurence Oberman wrote: > > Hello > > Its not going to be tens of thousands of devices. That count was an > > aggregate based on 1000's of servers. > > In reality its unlikely to ever be more than 100 tape

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-08 Thread Kai Mäkisara (Kolumbus)
> On 8.2.2015, at 4.45, Greg KH wrote: > > On Sat, Feb 07, 2015 at 09:27:05PM -0500, Laurence Oberman wrote: >> Hello >> Its not going to be tens of thousands of devices. That count was an >> aggregate based on 1000's of servers. >> In reality its unlikely to ever be more than 100 tapes drives p

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-07 Thread Greg KH
On Sat, Feb 07, 2015 at 09:27:05PM -0500, Laurence Oberman wrote: > Hello > Its not going to be tens of thousands of devices. That count was an > aggregate based on 1000's of servers. > In reality its unlikely to ever be more than 100 tapes drives per > individual Linux kernel instance. > Therefore

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-07 Thread Laurence Oberman
Hello Its not going to be tens of thousands of devices. That count was an aggregate based on 1000's of servers. In reality its unlikely to ever be more than 100 tapes drives per individual Linux kernel instance. Therefore sysfs will be the valid way to do this and make the data available to user sp

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-07 Thread Greg KH
On Fri, Feb 06, 2015 at 03:41:58PM +, Bryn M. Reeves wrote: > On Fri, Feb 06, 2015 at 04:59:16AM -0800, Greg KH wrote: > > On Fri, Feb 06, 2015 at 12:20:53AM +, Seymour, Shane M wrote: > > > The current patch that implements tape statistics is here: > > > > > > http://marc.info/?l=linux-sc

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-06 Thread Bryn M. Reeves
On Fri, Feb 06, 2015 at 04:59:16AM -0800, Greg KH wrote: > On Fri, Feb 06, 2015 at 12:20:53AM +, Seymour, Shane M wrote: > > The current patch that implements tape statistics is here: > > > > http://marc.info/?l=linux-scsi&m=142112067313723&w=2 > > Aside from the "do we want to do this all in

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-06 Thread Greg KH
On Fri, Feb 06, 2015 at 09:13:55AM +, Bryn M. Reeves wrote: > > The sysfs documentation says that files should contain one item per > > file (with some small exceptions): > > > > > "Attributes should be ASCII text files, preferably with only one value > > > per file. It is noted that it may no

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-06 Thread Greg KH
On Fri, Feb 06, 2015 at 12:20:53AM +, Seymour, Shane M wrote: > Hello linux-api'ers > > There has been some ongoing discussion about the best way to implement tape > statistics. The original method suggested a long time ago used a single file > in sysfs similar to block statistics in sysfs.

Re: [RFC] implementing tape statistics single file vs multi-file in sysfs

2015-02-06 Thread Bryn M. Reeves
On Fri, Feb 06, 2015 at 12:20:53AM +, Seymour, Shane M wrote: > There has been some ongoing discussion about the best way to implement > tape statistics. The original method suggested a long time ago used a > single file in sysfs similar to block statistics in sysfs. That lead to > an impass ab