On 10/13/20 8:12 AM, Mike Rapoport wrote: > On Tue, Oct 13, 2020 at 07:43:59AM -0700, Randy Dunlap wrote: >> On 10/13/20 1:09 AM, Mike Rapoport wrote: >>> On Mon, Oct 12, 2020 at 05:53:01PM +0800, Muchun Song wrote: >>>> On Mon, Oct 12, 2020 at 5:24 PM Eric Dumazet <eric.dumazet@xxxxxxxxx> wrote: >>>>> >>>>> On 10/12/20 10:39 AM, Muchun Song wrote: >>>>>> On Mon, Oct 12, 2020 at 3:42 PM Eric Dumazet <edumazet@xxxxxxxxxx> wrote: >>>> >>>> We are not complaining about TCP using too much memory, but how do >>>> we know that TCP uses a lot of memory. When I firstly face this problem, >>>> I do not know who uses the 25GB memory and it is not shown in the /proc/meminfo. >>>> If we can know the amount memory of the socket buffer via /proc/meminfo, we >>>> may not need to spend a lot of time troubleshooting this problem. Not everyone >>>> knows that a lot of memory may be used here. But I believe many people >>>> should know /proc/meminfo to confirm memory users. >>> >>> If I undestand correctly, the problem you are trying to solve is to >>> simplify troubleshooting of memory usage for people who may not be aware >>> that networking stack can be a large memory consumer. >>> >>> For that a paragraph in 'man 5 proc' maybe a good start: >>> >>> >From ddbcf38576d1a2b0e36fe25a27350d566759b664 Mon Sep 17 00:00:00 2001 >>> From: Mike Rapoport <rppt@xxxxxxxxxxxxx> >>> Date: Tue, 13 Oct 2020 11:07:35 +0300 >>> Subject: [PATCH] proc.5: meminfo: add not anout network stack memory >>> consumption >>> >>> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> >>> --- >>> man5/proc.5 | 8 ++++++++ >>> 1 file changed, 8 insertions(+) >>> >>> diff --git a/man5/proc.5 b/man5/proc.5 >>> index ed309380b..8414676f1 100644 >>> --- a/man5/proc.5 >>> +++ b/man5/proc.5 >>> @@ -3478,6 +3478,14 @@ Except as noted below, >>> all of the fields have been present since at least Linux 2.6.0. >>> Some fields are displayed only if the kernel was configured >>> with various options; those dependencies are noted in the list. >>> +.IP >>> +Note that significant part of memory allocated by the network stack >>> +is not accounted in the file. >>> +The memory consumption of the network stack can be queried >>> +using >>> +.IR /proc/net/sockstat >>> +or >>> +.BR ss (8) >>> .RS >>> .TP >>> .IR MemTotal " %lu" >> >> Hi Mike, >> >> Could you tell us what units those values are in? >> or is that already explained somewhere else? > > It is described a few lines above and anyway, "MemTotal" is a part of > the diff context ;-) with no units AFAICT. But I was unclear. I wasn't referring to /proc/meminfo, but instead to /proc/net/sockstat and its units: sockets: used 1224 TCP: inuse 11 orphan 1 tw 1 alloc 26 mem 3 UDP: inuse 4 mem 2 UDPLITE: inuse 0 RAW: inuse 0 FRAG: inuse 0 memory 0 E.g., for TCP and UDP, are those socket counts or some unit of memory? If units of memory, what unit size? thanks. -- ~Randy
