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: [PATCH] st: implement sysfs based tape statistics v2

2015-02-08 Thread Dale R. Worley
One feature of tape statistics is that they're as much about the *tape* as they are about the *drive*, which is uncommon for block devices. It might be useful to have a set of counters which is cleared every time a new tape is inserted into the drive. In particular, "bad reads since this tape was

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: Issues with commit 34b48db6 ("block: remove artifical max_hw_sectors cap")

2015-02-08 Thread Kenneth R. Crudup
On Mon, 19 Jan 2015, Alan Stern wrote: ... If anyone (still?) cares about this bug, commit 3a9794d3 ("sd: Fix max transfer length for 4k disks") fixes it, with no patches required. -Kenny -- Kenneth R. Crudup Sr. SW Engineer, Scott County Consulting, Silicon Valley -- To unsubscribe f

RE: [PATCH] st: implement sysfs based tape statistics v2

2015-02-08 Thread Seymour, Shane M
Both of those things would have to be futures and require discussion - the very original version cleared stats on a device open but I got asked to keep it the stats cumulative so they would be more similar to disk stats. I'm not sure about the bad reads idea I'd have to look and see if some othe

RE: [PATCH] st: implement sysfs based tape statistics v2

2015-02-08 Thread Seymour, Shane M
Kai - see last 3 paragraphs for question about if something is a bug or not. BTW I had a look - I couldn't quickly find out if there was a way to tell if the medium has changed in a tape drive (there could be something device specific). At the device level there's a record of I/O errors: [root@

[PATCH] st implement tape statistics v3

2015-02-08 Thread Seymour, Shane M
Hi All, Please find attached v3 of the patch. It implements the changes requested by Greg. The statistics files aren't in a separate directory any more they're implemented directly as device attributes unless someone has objections to them being in a place like /sys/class/scsi_tape/*/. There's

Re: [PATCH] xen-scsiback: some modifications about code comment

2015-02-08 Thread Juergen Gross
On 02/07/2015 04:31 AM, Rudy Zhang wrote: From: Tao Chen Signed-off-by: Tao Chen Are some white space fixes in comments really worth a patch? Juergen --- drivers/xen/xen-scsiback.c | 16 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/xen/xen-scsi