Messages in this thread | | | From | Praveen Kannoju <> | Subject | RE: [PATCH RFC] bonding: rate-limit bonding driver inspect messages | Date | Mon, 19 Feb 2024 11:35:32 +0000 |
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> -----Original Message----- > From: Hangbin Liu <liuhangbin@gmail.com> > Sent: 18 February 2024 08:39 AM > To: Praveen Kannoju <praveen.kannoju@oracle.com> > Cc: j.vosburgh@gmail.com; andy@greyhouse.net; davem@davemloft.net; edumazet@google.com; kuba@kernel.org; > pabeni@redhat.com; netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Rajesh Sivaramasubramaniom > <rajesh.sivaramasubramaniom@oracle.com>; Rama Nichanamatlu <rama.nichanamatlu@oracle.com>; Manjunath Patil > <manjunath.b.patil@oracle.com> > Subject: Re: [PATCH RFC] bonding: rate-limit bonding driver inspect messages > > On Sat, Feb 17, 2024 at 12:39:44PM +0000, Praveen Kannoju wrote: > > > -----Original Message----- > > > From: Hangbin Liu <liuhangbin@gmail.com> > > > Sent: 16 February 2024 02:33 PM > > > To: Praveen Kannoju <praveen.kannoju@oracle.com> > > > Cc: j.vosburgh@gmail.com; andy@greyhouse.net; davem@davemloft.net; > > > edumazet@google.com; kuba@kernel.org; pabeni@redhat.com; > > > netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Rajesh > > > Sivaramasubramaniom <rajesh.sivaramasubramaniom@oracle.com>; Rama > > > Nichanamatlu <rama.nichanamatlu@oracle.com>; Manjunath Patil > > > <manjunath.b.patil@oracle.com> > > > Subject: Re: [PATCH RFC] bonding: rate-limit bonding driver inspect > > > messages > > > > > > On Thu, Feb 15, 2024 at 10:55:54PM +0530, Praveen Kumar Kannoju wrote: > > > > Rate limit bond driver log messages, to prevent a log flood in a > > > > run-away situation, e.g couldn't get rtnl lock. Message flood > > > > leads to instability of system and loss of other crucial messages. > > > > > > Hi Praveen, > > > > > > The patch looks good to me. But would you please help explain why > > > these > > > slave_info() are chosen under net_ratelimit? > > > > > > Thanks > > > Hangbin > > > > Thank you, Hangbin. > > > > The routine bond_mii_monitor() periodically inspects the slave carrier state in order to detect for state changes, on a state change > internally records it and does the state change action. > > > > Parked-to-Parked state changes goes through transient state. As an example for Up to Down, BOND_LINK_UP to > BOND_LINK_DOWN, is thru BOND_LINK_FAIL. In order to attain next parked state or transient state bond needs rtnl mutex. If in a > situation it cannot get it, a state change wouldn't happen. In order to achieve a state change as quickly as possible > bond_mii_monitor() reschedules itself to come around after 1 msec. > > I think a large miimon downdelay/updelay setting could reduce this. > > > And every single come around reinspects the link and sees a state change compared to its internally recorded, which in reality > internal state could be not changed earlier as failed to get rtnl lock, and throws again log indicating it sees a state change. If attaining > rtnl mutex take long say hypothetical 5 secs, then bond logs 5000 state change message. 1 message at every 1 msec. > > Anyway, setting the rate limit do reduce the message flood. Would you please summarise the paragraph and add it in commit > description when post the formal patch? > > thanks > Hangbin
Thank you very much, Hangbin.
I've added the summary on why we intend to rate-limit the messages in the commit, and re-sent the formal patch.
- Praveen.
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