Bizarre benchmarking result while it generates TLS workloads to Redis

[eecheng87]

Hi, recently I tried to benchmark Redis with TLS loads. The server is built with the following commands:

# in redis-7.0.5
make BUILD_TLS=yes

# generate certificate
./utils/gen-test-certs.sh

memtier_benchmark is built with:

git clone https://github.com/RedisLabs/memtier_benchmark.git
cd memtier_benchmark/
autoreconf -ivf
./configure
make -j32

The server is launched by (I'm using OpenSSL 3.0.0) :

 ./src/redis-server --tls-port 6379 --port 0 \
                                       --tls-cert-file ./tests/tls/redis.crt \
                                       --tls-key-file ./tests/tls/redis.key \
                                       --tls-ca-cert-file ./tests/tls/ca.crt

The memtier_benchmark is executed as:

taskset --cpu-list 12-31 ./memtier_benchmark -p 6379 --protocol=redis --test-time=3 --hide-histogram --tls  \
--cert=/path/to/redis-7.0.5/tests/tls/redis.crt \
--key=/path/to/redis-7.0.5/tests/tls/redis.key \
--cacert=/path/to/redis-7.0.5/tests/tls/ca.crt

Then, I got the result like:

[RUN #1] Preparing benchmark client...
[RUN #1] Launching threads now...
[RUN #1 20%,   0 secs]  4 threads:           0 ops,       0 (avg:       0) ops/sec, 0.00KB/sec (avg: 0.00KB/sec),
[RUN #1 53%,   1 secs]  4 threads:       17658 ops,   17652 (avg:   11125) ops/sec, 753.52KB/sec (avg: 474.93KB/s
[RUN #1 86%,   2 secs]  4 threads:       50440 ops,   32771 (avg:   19494) ops/sec, 1.36MB/sec (avg: 828.86KB/sec
[RUN #1 100%,   3 secs]  0 threads:       71808 ops,   32771 (avg:   23920) ops/sec, 1.36MB/sec (avg: 1015.90KB/sec),  6.10 (avg:  8.36) msec latency

4         Threads
50        Connections per thread
3         Seconds

Is no request completed in 0 secs normal? I did not observe this behavior with non-TLS loads. Additionaly, if I increases the concurrency, the result becomes more weird. Here is another configuration for memtier_benchmark:

# memtier_benchmark
taskset --cpu-list 12-31 ./memtier_benchmark -p 6379 --protocol=redis --clients 25 --threads=20 --ratio=1:9 --key-pattern=R:R --key-minimum=1 --key-maximum=500 --data-size=32 --test-time=3 --hide-histogram --tls \
--cert=/path/to/redis-7.0.5/tests/tls/client.crt \
--key=/path/to/redis-7.0.5/tests/tls/client.key \
--cacert=/path/to/redis-7.0.5/tests/tls/ca.crt

# Result
[RUN #1] Preparing benchmark client...
[RUN #1] Launching threads now...
[RUN #1 10%,   0 secs] 20 threads:           0 ops,       0 (avg:       0) ops/sec, 0.00KB/sec (avg: 0.00KB/sec
[RUN #1 41%,   1 secs] 20 threads:           0 ops,       0 (avg:       0) ops/sec, 0.00KB/sec (avg: 0.00KB/sec
[RUN #1 74%,   2 secs] 20 threads:           0 ops,       0 (avg:       0) ops/sec, 0.00KB/sec (avg: 0.00KB/sec
[RUN #1 101%,   3 secs] 20 threads:       11611 ops,   14314 (avg:    3835) ops/sec, 660.57KB/sec (avg: 176.99K
[RUN #1 104%,   3 secs]  0 threads:       26266 ops,   14314 (avg:    8443) ops/sec, 660.57KB/sec (avg: 389.15KB/sec), 130.31 (avg: 59.20) msec latency