Re: [PATCH 0/4] io-controller: Add new interfaces to trace backloggedgroup status

From: Gui Jianfeng
Date: Sun May 23 2010 - 21:14:16 EST

Vivek Goyal wrote:
> On Fri, May 21, 2010 at 04:40:50PM +0800, Gui Jianfeng wrote:
>> Hi,
>> This series implements three new interfaces to keep track of tranferred bytes,
>> elapsing time and io rate since group getting backlogged. If the group dequeues
>> from service tree, these three interfaces will reset and shows zero.
> Hi Gui,
> Can you give some details regarding how this functionality is useful? Why
> would somebody be interested in only in stats of till group was
> backlogged and not in total stats?
> Groups can come and go so fast and these stats will reset so many times
> that I am not able to visualize how these stats will be useful.

Hi Vivek,

Currently, we assign weight to a group, but user still doesn't know how fast the
group runs. With io rate interface, users can check the rate of a group at any
moment, or to determine whether the weight assigned to a group is enough.
bytes and time interface is just for debug purpose.


> Thanks
> Vivek
>> Thanks
>> Gui
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