Commit Graph

3 Commits

Author SHA1 Message Date
Joanne Koong
ec151037af selftest/bpf/benchs: Add bpf_loop benchmark
Add benchmark to measure the throughput and latency of the bpf_loop
call.

Testing this on my dev machine on 1 thread, the data is as follows:

        nr_loops: 10
bpf_loop - throughput: 198.519 ± 0.155 M ops/s, latency: 5.037 ns/op

        nr_loops: 100
bpf_loop - throughput: 247.448 ± 0.305 M ops/s, latency: 4.041 ns/op

        nr_loops: 500
bpf_loop - throughput: 260.839 ± 0.380 M ops/s, latency: 3.834 ns/op

        nr_loops: 1000
bpf_loop - throughput: 262.806 ± 0.629 M ops/s, latency: 3.805 ns/op

        nr_loops: 5000
bpf_loop - throughput: 264.211 ± 1.508 M ops/s, latency: 3.785 ns/op

        nr_loops: 10000
bpf_loop - throughput: 265.366 ± 3.054 M ops/s, latency: 3.768 ns/op

        nr_loops: 50000
bpf_loop - throughput: 235.986 ± 20.205 M ops/s, latency: 4.238 ns/op

        nr_loops: 100000
bpf_loop - throughput: 264.482 ± 0.279 M ops/s, latency: 3.781 ns/op

        nr_loops: 500000
bpf_loop - throughput: 309.773 ± 87.713 M ops/s, latency: 3.228 ns/op

        nr_loops: 1000000
bpf_loop - throughput: 262.818 ± 4.143 M ops/s, latency: 3.805 ns/op

>From this data, we can see that the latency per loop decreases as the
number of loops increases. On this particular machine, each loop had an
overhead of about ~4 ns, and we were able to run ~250 million loops
per second.

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211130030622.4131246-5-joannekoong@fb.com
2021-11-30 10:56:28 -08:00
Joanne Koong
f44bc543a0 bpf/benchs: Add benchmarks for comparing hashmap lookups w/ vs. w/out bloom filter
This patch adds benchmark tests for comparing the performance of hashmap
lookups without the bloom filter vs. hashmap lookups with the bloom filter.

Checking the bloom filter first for whether the element exists should
overall enable a higher throughput for hashmap lookups, since if the
element does not exist in the bloom filter, we can avoid a costly lookup in
the hashmap.

On average, using 5 hash functions in the bloom filter tended to perform
the best across the widest range of different entry sizes. The benchmark
results using 5 hash functions (running on 8 threads on a machine with one
numa node, and taking the average of 3 runs) were roughly as follows:

value_size = 4 bytes -
	10k entries: 30% faster
	50k entries: 40% faster
	100k entries: 40% faster
	500k entres: 70% faster
	1 million entries: 90% faster
	5 million entries: 140% faster

value_size = 8 bytes -
	10k entries: 30% faster
	50k entries: 40% faster
	100k entries: 50% faster
	500k entres: 80% faster
	1 million entries: 100% faster
	5 million entries: 150% faster

value_size = 16 bytes -
	10k entries: 20% faster
	50k entries: 30% faster
	100k entries: 35% faster
	500k entres: 65% faster
	1 million entries: 85% faster
	5 million entries: 110% faster

value_size = 40 bytes -
	10k entries: 5% faster
	50k entries: 15% faster
	100k entries: 20% faster
	500k entres: 65% faster
	1 million entries: 75% faster
	5 million entries: 120% faster

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211027234504.30744-6-joannekoong@fb.com
2021-10-28 13:22:49 -07:00
Joanne Koong
57fd1c63c9 bpf/benchs: Add benchmark tests for bloom filter throughput + false positive
This patch adds benchmark tests for the throughput (for lookups + updates)
and the false positive rate of bloom filter lookups, as well as some
minor refactoring of the bash script for running the benchmarks.

These benchmarks show that as the number of hash functions increases,
the throughput and the false positive rate of the bloom filter decreases.
>From the benchmark data, the approximate average false-positive rates
are roughly as follows:

1 hash function = ~30%
2 hash functions = ~15%
3 hash functions = ~5%
4 hash functions = ~2.5%
5 hash functions = ~1%
6 hash functions = ~0.5%
7 hash functions  = ~0.35%
8 hash functions = ~0.15%
9 hash functions = ~0.1%
10 hash functions = ~0%

For reference data, the benchmarks run on one thread on a machine
with one numa node for 1 to 5 hash functions for 8-byte and 64-byte
values are as follows:

1 hash function:
  50k entries
	8-byte value
	    Lookups - 51.1 M/s operations
	    Updates - 33.6 M/s operations
	    False positive rate: 24.15%
	64-byte value
	    Lookups - 15.7 M/s operations
	    Updates - 15.1 M/s operations
	    False positive rate: 24.2%
  100k entries
	8-byte value
	    Lookups - 51.0 M/s operations
	    Updates - 33.4 M/s operations
	    False positive rate: 24.04%
	64-byte value
	    Lookups - 15.6 M/s operations
	    Updates - 14.6 M/s operations
	    False positive rate: 24.06%
  500k entries
	8-byte value
	    Lookups - 50.5 M/s operations
	    Updates - 33.1 M/s operations
	    False positive rate: 27.45%
	64-byte value
	    Lookups - 15.6 M/s operations
	    Updates - 14.2 M/s operations
	    False positive rate: 27.42%
  1 mil entries
	8-byte value
	    Lookups - 49.7 M/s operations
	    Updates - 32.9 M/s operations
	    False positive rate: 27.45%
	64-byte value
	    Lookups - 15.4 M/s operations
	    Updates - 13.7 M/s operations
	    False positive rate: 27.58%
  2.5 mil entries
	8-byte value
	    Lookups - 47.2 M/s operations
	    Updates - 31.8 M/s operations
	    False positive rate: 30.94%
	64-byte value
	    Lookups - 15.3 M/s operations
	    Updates - 13.2 M/s operations
	    False positive rate: 30.95%
  5 mil entries
	8-byte value
	    Lookups - 41.1 M/s operations
	    Updates - 28.1 M/s operations
	    False positive rate: 31.01%
	64-byte value
	    Lookups - 13.3 M/s operations
	    Updates - 11.4 M/s operations
	    False positive rate: 30.98%

2 hash functions:
  50k entries
	8-byte value
	    Lookups - 34.1 M/s operations
	    Updates - 20.1 M/s operations
	    False positive rate: 9.13%
	64-byte value
	    Lookups - 8.4 M/s operations
	    Updates - 7.9 M/s operations
	    False positive rate: 9.21%
  100k entries
	8-byte value
	    Lookups - 33.7 M/s operations
	    Updates - 18.9 M/s operations
	    False positive rate: 9.13%
	64-byte value
	    Lookups - 8.4 M/s operations
	    Updates - 7.7 M/s operations
	    False positive rate: 9.19%
  500k entries
	8-byte value
	    Lookups - 32.7 M/s operations
	    Updates - 18.1 M/s operations
	    False positive rate: 12.61%
	64-byte value
	    Lookups - 8.4 M/s operations
	    Updates - 7.5 M/s operations
	    False positive rate: 12.61%
  1 mil entries
	8-byte value
	    Lookups - 30.6 M/s operations
	    Updates - 18.9 M/s operations
	    False positive rate: 12.54%
	64-byte value
	    Lookups - 8.0 M/s operations
	    Updates - 7.0 M/s operations
	    False positive rate: 12.52%
  2.5 mil entries
	8-byte value
	    Lookups - 25.3 M/s operations
	    Updates - 16.7 M/s operations
	    False positive rate: 16.77%
	64-byte value
	    Lookups - 7.9 M/s operations
	    Updates - 6.5 M/s operations
	    False positive rate: 16.88%
  5 mil entries
	8-byte value
	    Lookups - 20.8 M/s operations
	    Updates - 14.7 M/s operations
	    False positive rate: 16.78%
	64-byte value
	    Lookups - 7.0 M/s operations
	    Updates - 6.0 M/s operations
	    False positive rate: 16.78%

3 hash functions:
  50k entries
	8-byte value
	    Lookups - 25.1 M/s operations
	    Updates - 14.6 M/s operations
	    False positive rate: 7.65%
	64-byte value
	    Lookups - 5.8 M/s operations
	    Updates - 5.5 M/s operations
	    False positive rate: 7.58%
  100k entries
	8-byte value
	    Lookups - 24.7 M/s operations
	    Updates - 14.1 M/s operations
	    False positive rate: 7.71%
	64-byte value
	    Lookups - 5.8 M/s operations
	    Updates - 5.3 M/s operations
	    False positive rate: 7.62%
  500k entries
	8-byte value
	    Lookups - 22.9 M/s operations
	    Updates - 13.9 M/s operations
	    False positive rate: 2.62%
	64-byte value
	    Lookups - 5.6 M/s operations
	    Updates - 4.8 M/s operations
	    False positive rate: 2.7%
  1 mil entries
	8-byte value
	    Lookups - 19.8 M/s operations
	    Updates - 12.6 M/s operations
	    False positive rate: 2.60%
	64-byte value
	    Lookups - 5.3 M/s operations
	    Updates - 4.4 M/s operations
	    False positive rate: 2.69%
  2.5 mil entries
	8-byte value
	    Lookups - 16.2 M/s operations
	    Updates - 10.7 M/s operations
	    False positive rate: 4.49%
	64-byte value
	    Lookups - 4.9 M/s operations
	    Updates - 4.1 M/s operations
	    False positive rate: 4.41%
  5 mil entries
	8-byte value
	    Lookups - 18.8 M/s operations
	    Updates - 9.2 M/s operations
	    False positive rate: 4.45%
	64-byte value
	    Lookups - 5.2 M/s operations
	    Updates - 3.9 M/s operations
	    False positive rate: 4.54%

4 hash functions:
  50k entries
	8-byte value
	    Lookups - 19.7 M/s operations
	    Updates - 11.1 M/s operations
	    False positive rate: 1.01%
	64-byte value
	    Lookups - 4.4 M/s operations
	    Updates - 4.0 M/s operations
	    False positive rate: 1.00%
  100k entries
	8-byte value
	    Lookups - 19.5 M/s operations
	    Updates - 10.9 M/s operations
	    False positive rate: 1.00%
	64-byte value
	    Lookups - 4.3 M/s operations
	    Updates - 3.9 M/s operations
	    False positive rate: 0.97%
  500k entries
	8-byte value
	    Lookups - 18.2 M/s operations
	    Updates - 10.6 M/s operations
	    False positive rate: 2.05%
	64-byte value
	    Lookups - 4.3 M/s operations
	    Updates - 3.7 M/s operations
	    False positive rate: 2.05%
  1 mil entries
	8-byte value
	    Lookups - 15.5 M/s operations
	    Updates - 9.6 M/s operations
	    False positive rate: 1.99%
	64-byte value
	    Lookups - 4.0 M/s operations
	    Updates - 3.4 M/s operations
	    False positive rate: 1.99%
  2.5 mil entries
	8-byte value
	    Lookups - 13.8 M/s operations
	    Updates - 7.7 M/s operations
	    False positive rate: 3.91%
	64-byte value
	    Lookups - 3.7 M/s operations
	    Updates - 3.6 M/s operations
	    False positive rate: 3.78%
  5 mil entries
	8-byte value
	    Lookups - 13.0 M/s operations
	    Updates - 6.9 M/s operations
	    False positive rate: 3.93%
	64-byte value
	    Lookups - 3.5 M/s operations
	    Updates - 3.7 M/s operations
	    False positive rate: 3.39%

5 hash functions:
  50k entries
	8-byte value
	    Lookups - 16.4 M/s operations
	    Updates - 9.1 M/s operations
	    False positive rate: 0.78%
	64-byte value
	    Lookups - 3.5 M/s operations
	    Updates - 3.2 M/s operations
	    False positive rate: 0.77%
  100k entries
	8-byte value
	    Lookups - 16.3 M/s operations
	    Updates - 9.0 M/s operations
	    False positive rate: 0.79%
	64-byte value
	    Lookups - 3.5 M/s operations
	    Updates - 3.2 M/s operations
	    False positive rate: 0.78%
  500k entries
	8-byte value
	    Lookups - 15.1 M/s operations
	    Updates - 8.8 M/s operations
	    False positive rate: 1.82%
	64-byte value
	    Lookups - 3.4 M/s operations
	    Updates - 3.0 M/s operations
	    False positive rate: 1.78%
  1 mil entries
	8-byte value
	    Lookups - 13.2 M/s operations
	    Updates - 7.8 M/s operations
	    False positive rate: 1.81%
	64-byte value
	    Lookups - 3.2 M/s operations
	    Updates - 2.8 M/s operations
	    False positive rate: 1.80%
  2.5 mil entries
	8-byte value
	    Lookups - 10.5 M/s operations
	    Updates - 5.9 M/s operations
	    False positive rate: 0.29%
	64-byte value
	    Lookups - 3.2 M/s operations
	    Updates - 2.4 M/s operations
	    False positive rate: 0.28%
  5 mil entries
	8-byte value
	    Lookups - 9.6 M/s operations
	    Updates - 5.7 M/s operations
	    False positive rate: 0.30%
	64-byte value
	    Lookups - 3.2 M/s operations
	    Updates - 2.7 M/s operations
	    False positive rate: 0.30%

Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211027234504.30744-5-joannekoong@fb.com
2021-10-28 13:22:49 -07:00