> -----Original Message----- > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Matthew Hall > Sent: Friday, September 11, 2015 6:18 PM > To: Vladislav Zolotarov > Cc: dev at dpdk.org > Subject: Re: [dpdk-dev] [PATCH v1] ixgbe_pmd: forbid tx_rs_thresh above 1 for > all NICs but 82598 > > On Fri, Sep 11, 2015 at 07:18:20PM +0300, Vladislav Zolotarov wrote: > > We thought about linearization too. It's doable with extra mempool and it > > may be optional so that those that don't need could compile it out and/or > > disable it in a runtime... > > High-level question. How realistic is sending a 40-segment frame in the first > place? This whole thing seems kind of academic to me unless I missed > something. > > I usually use 2K pktmbufs and I don't think this is an uncommon size. Most > jumbo frame hardware only does 9.5KB max frame size or so. > > So I am having a hard time imagining how I'd end up with more than 10 segments > as a worst-case scenario.
As I remember, with freebsd stack when TSO is on it was not unusual to see chains of ~30 segments. That's over port with 'normal' mtu (1.5K). Konstantin > > Matthew.
