On 1/19/17, 7:21 AM, Nogah Frankel wrote: >> -----Original Message----- >> From: Nogah Frankel >> Sent: Sunday, January 15, 2017 3:55 PM >> To: 'Stephen Hemminger' <step...@networkplumber.org> >> Cc: netdev@vger.kernel.org; roszenr...@gmail.com; ro...@cumulusnetworks.com; >> Jiri >> Pirko <j...@mellanox.com>; Ido Schimmel <ido...@mellanox.com>; Elad Raz >> <el...@mellanox.com>; Yotam Gigi <yot...@mellanox.com>; Or Gerlitz >> <ogerl...@mellanox.com> >> Subject: RE: [PATCH iproute2 v4 3/4] ifstat: Add 64 bits based stats to >> extended statistics >> >> >> >>> -----Original Message----- >>> From: Stephen Hemminger [mailto:step...@networkplumber.org] >>> Sent: Friday, January 13, 2017 3:44 AM >>> To: Nogah Frankel <nog...@mellanox.com> >>> Cc: netdev@vger.kernel.org; roszenr...@gmail.com; ro...@cumulusnetworks.com; >> Jiri >>> Pirko <j...@mellanox.com>; Ido Schimmel <ido...@mellanox.com>; Elad Raz >>> <el...@mellanox.com>; Yotam Gigi <yot...@mellanox.com>; Or Gerlitz >>> <ogerl...@mellanox.com> >>> Subject: Re: [PATCH iproute2 v4 3/4] ifstat: Add 64 bits based stats to >>> extended statistics >>> >>> On Thu, 12 Jan 2017 15:49:50 +0200 >>> Nogah Frankel <nog...@mellanox.com> wrote: >>> >>>> The default stats for ifstat are 32 bits based. >>>> The kernel supports 64 bits based stats. (They are returned in struct >>>> rtnl_link_stats64 which is an exact copy of struct rtnl_link_stats, in >>>> which the "normal" stats are returned, but with fields of u64 instead of >>>> u32). This patch adds them as an extended stats. >>>> >>>> It is read with filter type IFLA_STATS_LINK_64 and no sub type. >>>> >>>> It is under the name 64bits >>>> (or any shorten of it as "64") >>>> >>>> For example: >>>> ifstat -x 64bit >>>> >>>> Signed-off-by: Nogah Frankel <nog...@mellanox.com> >>>> Reviewed-by: Jiri Pirko <j...@mellanox.com> >>> Other commands (like ip link) always use the 64 bit statistics if available >>> from the device. I see no reason that ifstat needs to be different. >>> >> Do you mean to change the default ifstat results to be 64 bits based? >> I tried it in the first version, but Roopa commented that it was not a good >> idea. >> She said they tried it in the past and it caused backward compatibilities >> problems. >> (Or maybe I didn't understand correctly) > So, can I leave the default ifstat results to be 32 bits based, for the time > being? > >From past discussions: Moving the default to 64bit has compat issues with the >old history file. There is a way to make it work by using a new file header (to indicate that it is 64 bit) in a freshly created history file and also check this header before dumping stats into the history file. ie maintain backward compat without introducing a new option. It is doable.
One approach is, you can drop the 64bit option from this series and try updating the default to 64 bit (with compat handling code) in a later series.
