Re: [Cerowrt-devel] [Bloat] [Make-wifi-fast] TCP_NOTSENT_LOWAT applied to e2e TCP msg latency

--- Begin Message --- This is linux. The code flow is burst writes until the burst size, take a timestamp, call select(), take second timestamp and insert time delta into histogram, await clock_nanosleep() to schedule the next burst. (actually, the deltas, inserts into the histogram and user i/o

Re: [Cerowrt-devel] [Bloat] [Make-wifi-fast] TCP_NOTSENT_LOWAT applied to e2e TCP msg latency

On 10/26/21 4:38 PM, Christoph Paasch wrote: > Hi Bob, > >> On Oct 26, 2021, at 4:23 PM, Bob McMahon > > wrote: >> I'm confused. I don't see any blocking nor partial writes per the write() at >> the app level with TCP_NOTSENT_LOWAT set at 4 bytes. The burst is

Re: [Cerowrt-devel] [Bloat] [Make-wifi-fast] TCP_NOTSENT_LOWAT applied to e2e TCP msg latency

--- Begin Message --- I'm confused. I don't see any blocking nor partial writes per the write() at the app level with TCP_NOTSENT_LOWAT set at 4 bytes. The burst is 40K, the write size is 4K and the watermark is 4 bytes. There are ten writes per burst. The S8 histograms are the times waiting on

Re: [Cerowrt-devel] [Starlink] [Make-wifi-fast] TCP_NOTSENT_LOWAT applied to e2e TCP msg latency

--- Begin Message --- Hi Bjørn, I find, when possible, it's preferred to take telemetry data of actual traffic (or reads and writes) vs a proxy. We had a case where TCP BE was outperforming TCP w/VI because BE had the most engineering resources assigned to it and engineers did a better job with

[Cerowrt-devel] Fwd: [PATCH net-next] ifb: Depend on netfilter alternatively to tc

any benefits to getting away from mirred? -- Forwarded message - From: Lukas Wunner Date: Tue, Oct 26, 2021 at 12:11 AM Subject: [PATCH net-next] ifb: Depend on netfilter alternatively to tc To: David S. Miller , Jakub Kicinski Cc: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian

Re: [Cerowrt-devel] [Starlink] [Make-wifi-fast] TCP_NOTSENT_LOWAT applied to e2e TCP msg latency

Hi Bob, My name is Bjørn Ivar Teigen and I'm working on modeling and measuring WiFi MAC-layer protocol performance for my PhD. Is it necessary to measure the latency using the TCP stream itself? I had a similar problem in the past, and solved it by doing the latency measurements using TWAMP

Re: [Cerowrt-devel] [Make-wifi-fast] TCP_NOTSENT_LOWAT applied to e2e TCP msg latency

--- Begin Message --- On 21 Oct 2021, at 17:51, Bob McMahon via Make-wifi-fast wrote: > Hi All, > > Sorry for the spam. I'm trying to support a meaningful TCP message latency > w/iperf 2 from the sender side w/o requiring e2e clock synchronization. I > thought I'd try to use the