There are a couple of typos, fix these. Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Script for testing HBM (Host Bandwidth Manager) framework.
It creates a cgroup to use for testing and load a BPF program to limit
egress bandwidht. It then uses iperf3 or netperf to create
loads. The output is the goodput in Mbps (unless -D is used).
It can work on a single host using loopback or among two hosts (with netperf).
When using loopback, it is recommended to also introduce a delay of at least
1ms (-d=1), otherwise the assigned bandwidth is likely to be underutilized.
USAGE: $name [out] [-b=<prog>|--bpf=<prog>] [-c=<cc>|--cc=<cc>] [-D]
[-d=<delay>|--delay=<delay>] [--debug] [-E]
[-f=<#flows>|--flows=<#flows>] [-h] [-i=<id>|--id=<id >] [-l]
[-N] [-p=<port>|--port=<port>] [-P] [-q=<qdisc>]
[-R] [-s=<server>|--server=<server] [--stats]
[-t=<time>|--time=<time>] [-w] [cubic|dctcp]
Where:
out Egress (default egress)
-b or --bpf BPF program filename to load and attach.
Default is nrm_out_kern.o for egress,
-c or -cc TCP congestion control (cubic or dctcp)
-d or --delay Add a delay in ms using netem
-D In addition to the goodput in Mbps, it also outputs
other detailed information. This information is
test dependent (i.e. iperf3 or netperf).
--debug Print BPF trace buffer
-E Enable ECN (not required for dctcp)
-f or --flows Number of concurrent flows (default=1)
-i or --id cgroup id (an integer, default is 1)
-l Do not limit flows using loopback
-N Use netperf instead of iperf3
-h Help
-p or --port iperf3 port (default is 5201)
-P Use an iperf3 instance for each flow
-q Use the specified qdisc.
-r or --rate Rate in Mbps (default 1s 1Gbps)
-R Use TCP_RR for netperf. 1st flow has req
size of 10KB, rest of 1MB. Reply in all
cases is 1 byte.
More detailed output for each flow can be found
in the files netperf.<cg>.<flow>, where <cg> is the
cgroup id as specified with the -i flag, and <flow>
is the flow id starting at 1 and increasing by 1 for
flow (as specified by -f).
-s or --server hostname of netperf server. Used to create netperf
test traffic between to hosts (default is within host)
netserver must be running on the host.
--stats Get HBM stats (marked, dropped, etc.)
-t or --time duration of iperf3 in seconds (default=5)
-w Work conserving flag. cgroup can increase its
bandwidth beyond the rate limit specified
while there is available bandwidth. Current
implementation assumes there is only one NIC
(eth0), but can be extended to support multiple
NICs. This is just a proof of concept.
cubic or dctcp specify TCP CC to use
Examples:
./do_hbm_test.sh -l -d=1 -D --stats
Runs a 5 second test, using a single iperf3 flow and with the default
rate limit of 1Gbps and a delay of 1ms (using netem) using the default
TCP congestion control on the loopback device (hence we use "-l" to
enforce bandwidth limit on loopback device). Since no direction is
specified, it defaults to egress. Since no TCP CC algorithm is
specified it uses the system default (Cubic for this test).
With no -D flag, only the value of the AGGREGATE OUTPUT would show.
id refers to the cgroup id and is useful when running multi cgroup
tests (supported by a future patch).
This patchset does not support calling TCP's congesion window
reduction, even when packets are dropped by the BPF program, resulting
in a large number of packets dropped. It is recommended that the current
HBM implemenation only be used with ECN enabled flows. A future patch
will add support for reducing TCP's cwnd and will increase the
performance of non-ECN enabled flows.
Output:
Details for HBM in cgroup 1
id:1
rate_mbps:493
duration:4.8 secs
packets:11355
bytes_MB:590
pkts_dropped:4497
bytes_dropped_MB:292
pkts_marked_percent: 39.60
bytes_marked_percent: 49.49
pkts_dropped_percent: 39.60
bytes_dropped_percent: 49.49
PING AVG DELAY:2.075
AGGREGATE_GOODPUT:505
./do_nrm_test.sh -l -d=1 -D --stats dctcp
Same as above but using dctcp. Note that fewer bytes are dropped
(0.01% vs. 49%).
Output:
Details for HBM in cgroup 1
id:1
rate_mbps:945
duration:4.9 secs
packets:16859
bytes_MB:578
pkts_dropped:1
bytes_dropped_MB:0
pkts_marked_percent: 28.74
bytes_marked_percent: 45.15
pkts_dropped_percent: 0.01
bytes_dropped_percent: 0.01
PING AVG DELAY:2.083
AGGREGATE_GOODPUT:965
./do_nrm_test.sh -d=1 -D --stats
As first example, but without limiting loopback device (i.e. no
"-l" flag). Since there is no bandwidth limiting, no details for
HBM are printed out.
Output:
Details for HBM in cgroup 1
PING AVG DELAY:2.019
AGGREGATE_GOODPUT:42655
./do_hbm.sh -l -d=1 -D --stats -f=2
Uses iper3 and does 2 flows
./do_hbm.sh -l -d=1 -D --stats -f=4 -P
Uses iperf3 and does 4 flows, each flow as a separate process.
./do_hbm.sh -l -d=1 -D --stats -f=4 -N
Uses netperf, 4 flows
./do_hbm.sh -f=1 -r=2000 -t=5 -N -D --stats dctcp -s=<server-name>
Uses netperf between two hosts. The remote host name is specified
with -s= and you need to start the program netserver manually on
the remote host. It will use 1 flow, a rate limit of 2Gbps and dctcp.
./do_hbm.sh -f=1 -r=2000 -t=5 -N -D --stats -w dctcp \
-s=<server-name>
As previous, but allows use of extra bandwidth. For this test the
rate is 8Gbps vs. 1Gbps of the previous test.
Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The program nrm creates a cgroup and attaches a BPF program to the
cgroup for testing HBM (Host Bandwidth Manager) for egress traffic.
One still needs to create network traffic. This can be done through
netesto, netperf or iperf3.
A follow-up patch contains a script to create traffic.
USAGE: hbm [-d] [-l] [-n <id>] [-r <rate>] [-s] [-t <secs>]
[-w] [-h] [prog]
Where:
-d Print BPF trace debug buffer
-l Also limit flows doing loopback
-n <#> To create cgroup "/hbm#" and attach prog. Default is /nrm1
This is convenient when testing HBM in more than 1 cgroup
-r <rate> Rate limit in Mbps
-s Get HBM stats (marked, dropped, etc.)
-t <time> Exit after specified seconds (deault is 0)
-w Work conserving flag. cgroup can increase its bandwidth
beyond the rate limit specified while there is available
bandwidth. Current implementation assumes there is only
NIC (eth0), but can be extended to support multiple NICs.
Currrently only supported for egress. Note, this is just
a proof of concept.
-h Print this info
prog BPF program file name. Name defaults to hbm_out_kern.o
More information about HBM can be found in the paper "BPF Host Resource
Management" presented at the 2018 Linux Plumbers Conference, Networking Track
(http://vger.kernel.org/lpc_net2018_talks/LPC%20BPF%20Network%20Resource%20Paper.pdf)
Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
A cgroup skb BPF program to limit cgroup output bandwidth.
It uses a modified virtual token bucket queue to limit average
egress bandwidth. The implementation uses credits instead of tokens.
Negative credits imply that queueing would have happened (this is
a virtual queue, so no queueing is done by it. However, queueing may
occur at the actual qdisc (which is not used for rate limiting).
This implementation uses 3 thresholds, one to start marking packets and
the other two to drop packets:
CREDIT
- <--------------------------|------------------------> +
| | | 0
| Large pkt |
| drop thresh |
Small pkt drop Mark threshold
thresh
The effect of marking depends on the type of packet:
a) If the packet is ECN enabled, then the packet is ECN ce marked.
The current mark threshold is tuned for DCTCP.
c) Else, it is dropped if it is a large packet.
If the credit is below the drop threshold, the packet is dropped.
Note that dropping a packet through the BPF program does not trigger CWR
(Congestion Window Reduction) in TCP packets. A future patch will add
support for triggering CWR.
This BPF program actually uses 2 drop thresholds, one threshold
for larger packets (>= 120 bytes) and another for smaller packets. This
protects smaller packets such as SYNs, ACKs, etc.
The default bandwidth limit is set at 1Gbps but this can be changed by
a user program through a shared BPF map. In addition, by default this BPF
program does not limit connections using loopback. This behavior can be
overwritten by the user program. There is also an option to calculate
some statistics, such as percent of packets marked or dropped, which
the user program can access.
A latter patch provides such a program (hbm.c)
Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Compiling xdpsock_user.c with 4.8.5, I hit the following
compilation warning:
HOSTCC samples/bpf/xdpsock_user.o
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c: In function ‘main’:
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:449:6: warning: ‘idx_cq’ may be used unini
tialized in this function [-Wmaybe-uninitialized]
u32 idx_cq, idx_fq;
^
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:606:7: warning: ‘idx_rx’ may be used unini
tialized in this function [-Wmaybe-uninitialized]
u32 idx_rx, idx_tx = 0;
^
/data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:506:6: warning: ‘idx_rx’ may be used unini
tialized in this function [-Wmaybe-uninitialized]
u32 idx_rx, idx_fq = 0;
As an example, the code pattern looks like:
u32 idx_cq;
...
ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd, &idx_fq);
if (ret) {
...
}
... idx_fq ...
The compiler warns since it does not know whether &idx_fq is assigned
or not inside the library function xsk_ring_prod__reserve().
Let us assign an initial value 0 to such auto variables to silence
compiler warning.
Fixes: 248c7f9c0e21 ("samples/bpf: convert xdpsock to use libbpf for AF_XDP access")
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Some samples don't really need the magic of bpf_load, switch them to libbpf. v2: - specify program types. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpftool can do all the things load_sock_ops used to do, and more. Point users to bpftool instead of maintaining this sample utility. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
ping localhost may default of IPv6 on modern systems, but samples are trying to only parse IPv4. Force IPv4. samples/bpf/tracex1_user.c doesn't interpret the packet so we don't care which IP version will be used there. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, running sample "task_fd_query" and "tracex3" occurs the following error. On kernel v5.0-rc* this sample will be unavailable due to the removal of function 'blk_start_request' at commit "a1ce35f". (function removed, as "Single Queue IO scheduler" no longer exists) $ sudo ./task_fd_query failed to create kprobe 'blk_start_request' error 'No such file or directory' This commit will change the function 'blk_start_request' to 'blk_mq_start_request' to fix the broken sample. Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit converts the xdpsock sample application to use the AF_XDP functions present in libbpf. This cuts down the size of it by nearly 300 lines of code. The default ring sizes plus the batch size has been increased and the size of the umem area has decreased. This so that the sample application will provide higher throughput. Note also that the shared umem code has been removed from the sample as this is not supported by libbpf at this point in time. Tested-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>