On 14/04/2024 06:02, Wen Gu wrote:
This patch set acts as the second part of the new version of [1] (The first
part can be referred from [2]), the updated things of this version are listed
at the end.
- Background
SMC-D is now used in IBM z with ISM function to optimize network interconnect
for intra-CPC communications. Inspired by this, we try to make SMC-D available
on the non-s390 architecture through a software-implemented Emulated-ISM device,
that is the loopback-ism device here, to accelerate inter-process or
inter-containers communication within the same OS instance.
- Design
This patch set includes 3 parts:
- Patch #1: some prepare work for loopback-ism.
- Patch #2-#7: implement loopback-ism device and adapt SMC-D for it.
loopback-ism now serves only SMC and no userspace interfaces exposed.
- Patch #8-#11: memory copy optimization for intra-OS scenario.
The loopback-ism device is designed as an ISMv2 device and not be limited to
a specific net namespace, ends of both inter-process connection (1/1' in diagram
below) or inter-container connection (2/2' in diagram below) can find the same
available loopback-ism and choose it during the CLC handshake.
Container 1 (ns1) Container 2 (ns2)
+-----------------------------------------+ +-------------------------+
| +-------+ +-------+ +-------+ | | +-------+ |
| | App A | | App B | | App C | | | | App D |<-+ |
| +-------+ +---^---+ +-------+ | | +-------+ |(2') |
| |127.0.0.1 (1')| |192.168.0.11 192.168.0.12| |
| (1)| +--------+ | +--------+ |(2) | | +--------+ +--------+ |
| `-->| lo |-` | eth0 |<-` | | | lo | | eth0 | |
+---------+--|---^-+---+-----|--+---------+ +-+--------+---+-^------+-+
| | | |
Kernel | | | |
+----+-------v---+-----------v----------------------------------+---+----+
| | TCP | |
| | | |
| +--------------------------------------------------------------+ |
| |
| +--------------+ |
| | smc loopback | |
+---------------------------+--------------+-----------------------------+
loopback-ism device creates DMBs (shared memory) for each connection peer.
Since data transfer occurs within the same kernel, the sndbuf of each peer
is only a descriptor and point to the same memory region as peer DMB, so that
the data copy from sndbuf to peer DMB can be avoided in loopback-ism case.
Container 1 (ns1) Container 2 (ns2)
+-----------------------------------------+ +-------------------------+
| +-------+ | | +-------+ |
| | App C |-----+ | | | App D | |
| +-------+ | | | +-^-----+ |
| | | | | |
| (2) | | | (2') | |
| | | | | |
+---------------|-------------------------+ +----------|--------------+
| |
Kernel | |
+---------------|-----------------------------------------|--------------+
| +--------+ +--v-----+ +--------+ +--------+ |
| |dmb_desc| |snd_desc| |dmb_desc| |snd_desc| |
| +-----|--+ +--|-----+ +-----|--+ +--------+ |
| +-----|--+ | +-----|--+ |
| | DMB C | +---------------------------------| DMB D | |
| +--------+ +--------+ |
| |
| +--------------+ |
| | smc loopback | |
+---------------------------+--------------+-----------------------------+
- Benchmark Test
* Test environments:
- VM with Intel Xeon Platinum 8 core 2.50GHz, 16 GiB mem.
- SMC sndbuf/DMB size 1MB.
* Test object:
- TCP: run on TCP loopback.
- SMC lo: run on SMC loopback-ism.
1. ipc-benchmark (see [3])
- ./<foo> -c 1000000 -s 100
TCP SMC-lo
Message
rate (msg/s) 79693 148236(+86.01%)
2. sockperf
- serv: <smc_run> sockperf sr --tcp
- clnt: <smc_run> sockperf { tp | pp } --tcp --msg-size={ 64000 for tp | 14 for pp } -i 127.0.0.1 -t 30
TCP SMC-lo
Bandwidth(MBps) 4815.18 8061.77(+67.42%)
Latency(us) 6.176 3.449(-44.15%)
3. nginx/wrk
- serv: <smc_run> nginx
- clnt: <smc_run> wrk -t 8 -c 1000 -d 30 http://127.0.0.1:80
TCP SMC-lo
Requests/s 196555.02 263270.95(+33.94%)
4. redis-benchmark
- serv: <smc_run> redis-server
- clnt: <smc_run> redis-benchmark -h 127.0.0.1 -q -t set,get -n 400000 -c 200 -d 1024
TCP SMC-lo
GET(Requests/s) 88711.47 120048.02(+35.32%)
SET(Requests/s) 89465.44 123152.71(+37.65%)
Hi Wen Gu,
I did run the tests again with the v6 and reviewed the patchset. If you
decide to address Simons nit feel free to add my:
Reviewed-and-tested-by: Jan Karcher <jaka@xxxxxxxxxxxxx>
Thanks for your effort and contribution.
- J
