fasthttp.ServeFile can be too slow in some cases. #931
Comments
|
Which version of Go are you using? Which OS are you running? This is the exact result I'm getting with your repo: And this when I change it to |
|
Thank you for your time. I have also tested it on three other machines. On two of them it is as slow as my system but in one of them it is fast. That one is a Ubuntu Server 20.04. I've just copied my go binaries compiled on my personal pc to it and ran it. Do you have any idea how can I help to debug it? Why |
|
You can use https://pkg.go.dev/github.com/valyala/fasthttp/pprofhandler for pprof. I have tried this myself but couldn't get anything useful out of it. I have an Ubuntu 18.04.4 server with go1.15.3 which has the same issue. This is the simplest code to reproduce it within type bigFileReader struct {
f *os.File
}
func (r *bigFileReader) WriteTo(w io.Writer) (int64, error) {
if rf, ok := w.(io.ReaderFrom); ok {
return rf.ReadFrom(r.f)
}
panic("never reached")
}
func (r *bigFileReader) Read(p []byte) (int, error) {
return r.f.Read(p)
}
func (r *bigFileReader) Close() error {
return r.f.Close()
}
func serveWithReadingFile(ctx *fasthttp.RequestCtx) {
s, err := os.Stat(image_path)
if err != nil {
panic(err)
}
f, err := os.Open(image_path)
if err != nil {
panic(err)
}
ctx.SetBodyStream(&bigFileReader{
f: f,
}, int(s.Size()))
}This is slow for me. But if I comment out the I didn't have more time to look into this but it might be related to golang/go#41513 or golang/go#30377 |
|
I have looked a bit more into the issue and the real issue seems to be this Flush call: Lines 1743 to 1745 in 70e00dc I guess it causes 2 extra round trips. The flush is required to have an empty send buffer to trigger sendfile.
I think we should look into changing the threshold for which we try to trigger |
|
FYI, image details.. user@host:fs-is-slow$ ls -alt image* user@host:fs-is-slow$ file image2.jpg user@host:fs-is-slow$ file image1.jpg |
|
I have created a program to benchmark sendfile with net/http. Here are the results for several OSes all on a 16 core VMs: Ubuntu 20.04 size: sendfile vs r/w sendfile faster
1.0kb: 706.60 vs 20427.90 diff -2791.01%
2.0kb: 716.80 vs 21222.10 diff -2860.67%
3.0kb: 702.80 vs 21430.70 diff -2949.33%
4.0kb: 729.60 vs 20412.00 diff -2697.70%
5.0kb: 715.10 vs 20364.10 diff -2747.73%
6.0kb: 725.50 vs 20472.50 diff -2721.85%
7.0kb: 716.80 vs 20137.60 diff -2709.38%
8.0kb: 726.40 vs 20335.70 diff -2699.52%
9.0kb: 729.60 vs 20329.50 diff -2686.39%
10.0kb: 719.70 vs 20018.20 diff -2681.46%
20.0kb: 715.20 vs 19806.10 diff -2669.31%
30.0kb: 717.50 vs 19337.00 diff -2595.05%
40.0kb: 722.30 vs 18998.80 diff -2530.32%
50.0kb: 718.50 vs 18153.00 diff -2426.51%
60.0kb: 710.00 vs 18336.30 diff -2482.58%
66.0kb: 713.20 vs 17793.70 diff -2394.91%
66.0kb: 44677.30 vs 17552.00 diff 60.71%
70.0kb: 43157.90 vs 17540.80 diff 59.36%
80.0kb: 42678.50 vs 16633.60 diff 61.03%
90.0kb: 43080.00 vs 17348.00 diff 59.73%
100.0kb: 17737.20 vs 16612.30 diff 6.34%
200.0kb: 3894.60 vs 14035.10 diff -260.37%
300.0kb: 2343.60 vs 12395.80 diff -428.92%
400.0kb: 2779.30 vs 11168.40 diff -301.84%
500.0kb: 1833.50 vs 10121.80 diff -452.05%
600.0kb: 2215.50 vs 9272.90 diff -318.55%
700.0kb: 1661.70 vs 8337.10 diff -401.72%
800.0kb: 1846.80 vs 7572.50 diff -310.03%
900.0kb: 1657.80 vs 7347.50 diff -343.21%
1.0mb: 1753.40 vs 6943.90 diff -296.02%
1.1mb: 1414.30 vs 6497.10 diff -359.39%
1.2mb: 1606.20 vs 6094.20 diff -279.42%
1.5mb: 1332.50 vs 5383.30 diff -304.00%
2.0mb: 1386.80 vs 4392.60 diff -216.74%
2.5mb: 1662.10 vs 3744.00 diff -125.26%
3.0mb: 1272.90 vs 3235.80 diff -154.21%
100.0mb: 257.80 vs 153.30 diff 40.54%
200.0mb: 129.50 vs 77.10 diff 40.46%
300.0mb: 86.70 vs 51.90 diff 40.14%
400.0mb: 65.30 vs 39.20 diff 39.97%
500.0mb: 52.70 vs 31.70 diff 39.85%
600.0mb: 44.00 vs 26.90 diff 38.86%
700.0mb: 38.10 vs 22.90 diff 39.90%
800.0mb: 33.70 vs 20.50 diff 39.17%
900.0mb: 30.10 vs 18.80 diff 37.54%
1.0gb: 27.10 vs 16.10 diff 40.59%
Debian 10 size: sendfile vs r/w sendfile faster
1.0kb: 201.80 vs 20966.30 diff -10289.64%
2.0kb: 201.70 vs 21670.70 diff -10644.03%
3.0kb: 201.80 vs 21660.60 diff -10633.70%
4.0kb: 208.00 vs 20871.90 diff -9934.57%
5.0kb: 208.00 vs 21122.40 diff -10055.00%
6.0kb: 317.90 vs 20551.70 diff -6364.83%
7.0kb: 208.00 vs 20482.60 diff -9747.40%
8.0kb: 208.00 vs 19182.00 diff -9122.12%
9.0kb: 208.00 vs 20252.30 diff -9636.68%
10.0kb: 208.00 vs 20057.40 diff -9542.98%
20.0kb: 208.00 vs 19366.20 diff -9210.67%
30.0kb: 208.00 vs 19300.80 diff -9179.23%
40.0kb: 206.20 vs 18349.20 diff -8798.74%
50.0kb: 208.00 vs 17927.90 diff -8519.18%
60.0kb: 207.10 vs 16962.30 diff -8090.39%
66.0kb: 206.70 vs 17446.60 diff -8340.54%
66.0kb: 49166.10 vs 17233.00 diff 64.95%
70.0kb: 47402.80 vs 17020.20 diff 64.09%
80.0kb: 45941.10 vs 16996.30 diff 63.00%
90.0kb: 13578.30 vs 16769.40 diff -23.50%
100.0kb: 9143.20 vs 14763.30 diff -61.47%
200.0kb: 7409.70 vs 13496.30 diff -82.14%
300.0kb: 8566.60 vs 11609.40 diff -35.52%
400.0kb: 9131.60 vs 10333.40 diff -13.16%
500.0kb: 8884.00 vs 8548.70 diff 3.77%
600.0kb: 10724.40 vs 8382.90 diff 21.83%
700.0kb: 7439.70 vs 7432.80 diff 0.09%
800.0kb: 8889.10 vs 6632.10 diff 25.39%
900.0kb: 8299.80 vs 6481.90 diff 21.90%
1.0mb: 8757.70 vs 6088.40 diff 30.48%
1.1mb: 7156.50 vs 5664.00 diff 20.86%
1.2mb: 7668.40 vs 5404.60 diff 29.52%
1.5mb: 5676.80 vs 4756.50 diff 16.21%
2.0mb: 5180.20 vs 3838.40 diff 25.90%
2.5mb: 5237.20 vs 3252.20 diff 37.90%
3.0mb: 4385.60 vs 2845.50 diff 35.12%
100.0mb: 234.10 vs 143.40 diff 38.74%
200.0mb: 119.30 vs 73.10 diff 38.73%
300.0mb: 80.80 vs 49.80 diff 38.37%
400.0mb: 60.50 vs 37.70 diff 37.69%
500.0mb: 47.20 vs 29.50 diff 37.50%
600.0mb: 41.10 vs 25.70 diff 37.47%
700.0mb: 35.30 vs 22.20 diff 37.11%
800.0mb: 31.10 vs 19.40 diff 37.62%
900.0mb: 27.90 vs 17.50 diff 37.28%
1.0gb: 25.30 vs 16.00 diff 36.76%
Centos 8 size: sendfile vs r/w sendfile faster
1.0kb: 764.90 vs 20628.20 diff -2596.85%
2.0kb: 764.80 vs 18279.40 diff -2290.09%
3.0kb: 764.80 vs 20545.30 diff -2586.36%
4.0kb: 778.00 vs 18653.80 diff -2297.66%
5.0kb: 777.90 vs 18570.10 diff -2287.21%
6.0kb: 777.60 vs 18715.50 diff -2306.83%
7.0kb: 778.10 vs 18306.40 diff -2252.71%
8.0kb: 777.70 vs 18290.90 diff -2251.92%
9.0kb: 777.00 vs 18270.80 diff -2251.45%
10.0kb: 778.00 vs 18796.20 diff -2315.96%
20.0kb: 777.80 vs 17977.70 diff -2211.35%
30.0kb: 777.60 vs 17915.40 diff -2203.94%
40.0kb: 774.20 vs 16693.60 diff -2056.24%
50.0kb: 775.50 vs 16459.60 diff -2022.45%
60.0kb: 775.90 vs 16354.20 diff -2007.77%
66.0kb: 775.10 vs 15420.60 diff -1889.50%
66.0kb: 45815.40 vs 15569.60 diff 66.02%
70.0kb: 43780.20 vs 15241.20 diff 65.19%
80.0kb: 42914.80 vs 15287.80 diff 64.38%
90.0kb: 42403.80 vs 15031.60 diff 64.55%
100.0kb: 41484.70 vs 14082.20 diff 66.05%
200.0kb: 6354.20 vs 11793.60 diff -85.60%
300.0kb: 3735.10 vs 10085.10 diff -170.01%
400.0kb: 3841.30 vs 9022.90 diff -134.89%
500.0kb: 2897.80 vs 7702.20 diff -165.79%
600.0kb: 3122.80 vs 7402.00 diff -137.03%
700.0kb: 2737.40 vs 6899.40 diff -152.04%
800.0kb: 2967.30 vs 6377.70 diff -114.93%
900.0kb: 2412.20 vs 5992.60 diff -148.43%
1.0mb: 2724.20 vs 5630.20 diff -106.67%
1.1mb: 2232.40 vs 5330.50 diff -138.78%
1.2mb: 2677.00 vs 5040.30 diff -88.28%
1.5mb: 2146.70 vs 4345.20 diff -102.41%
2.0mb: 2445.70 vs 3532.60 diff -44.44%
2.5mb: 2465.20 vs 3072.20 diff -24.62%
3.0mb: 2017.90 vs 2672.20 diff -32.42%
100.0mb: 211.60 vs 130.50 diff 38.33%
200.0mb: 105.20 vs 66.30 diff 36.98%
300.0mb: 71.20 vs 44.70 diff 37.22%
400.0mb: 53.60 vs 34.30 diff 36.01%
500.0mb: 42.80 vs 27.70 diff 35.28%
600.0mb: 36.70 vs 22.80 diff 37.87%
700.0mb: 31.40 vs 19.60 diff 37.58%
800.0mb: 27.90 vs 18.20 diff 34.77%
900.0mb: 25.20 vs 16.00 diff 36.51%
1.0gb: 22.10 vs 14.20 diff 35.75%
As you can see sendfile is somehow very very slow for small files. With each OS there is a big bump in performance between 65994 and 65995 bytes. This seems to be the boundary of a TCP packet (minus http header). Not sure why this affects sendfile so much. I have also written something similar with fasthttp and how fasthttp.FS is implemented. Here is the result: Ubuntu 20.04 size: sendfile vs r/w sendfile faster
1.0kb: 102157.40 vs 100718.10 diff 1.41%
2.0kb: 100855.60 vs 100145.40 diff 0.70%
3.0kb: 102315.70 vs 100877.00 diff 1.41%
4.0kb: 91688.10 vs 91279.40 diff 0.45%
5.0kb: 91533.20 vs 91657.00 diff -0.14%
6.0kb: 92218.00 vs 91542.00 diff 0.73%
7.0kb: 91510.60 vs 88140.40 diff 3.68%
8.0kb: 92169.30 vs 91326.60 diff 0.91%
9.0kb: 208.00 vs 30026.50 diff -14335.82%
10.0kb: 208.00 vs 30227.40 diff -14432.40%
20.0kb: 208.10 vs 27823.30 diff -13270.16%
30.0kb: 208.10 vs 29558.10 diff -14103.80%
40.0kb: 207.20 vs 27734.00 diff -13285.14%
50.0kb: 207.90 vs 27146.60 diff -12957.53%
60.0kb: 207.80 vs 26804.90 diff -12799.37%
66.0kb: 24400.10 vs 25842.80 diff -5.91%
66.0kb: 25818.70 vs 25834.50 diff -0.06%
70.0kb: 17558.20 vs 25866.10 diff -47.32%
80.0kb: 9746.00 vs 25937.90 diff -166.14%
90.0kb: 6035.00 vs 24295.10 diff -302.57%
100.0kb: 4669.40 vs 24210.80 diff -418.50%
200.0kb: 12654.30 vs 19986.90 diff -57.95%
300.0kb: 5805.80 vs 16814.10 diff -189.61%
400.0kb: 12378.20 vs 14671.90 diff -18.53%
500.0kb: 8753.00 vs 13010.70 diff -48.64%
600.0kb: 13208.40 vs 11797.80 diff 10.68%
700.0kb: 9873.50 vs 10761.70 diff -9.00%
800.0kb: 12430.10 vs 9779.30 diff 21.33%
900.0kb: 8735.60 vs 9081.70 diff -3.96%
1.0mb: 10430.80 vs 8398.00 diff 19.49%
1.1mb: 7282.60 vs 7872.50 diff -8.10%
1.2mb: 9467.60 vs 7400.40 diff 21.83%
1.5mb: 6826.30 vs 6301.20 diff 7.69%
2.0mb: 6858.80 vs 5096.70 diff 25.69%
2.5mb: 6242.80 vs 4280.40 diff 31.43%
3.0mb: 5157.60 vs 3706.90 diff 28.13%
100.0mb: 248.50 vs 151.30 diff 39.11%
200.0mb: 124.60 vs 76.10 diff 38.92%
300.0mb: 83.40 vs 51.90 diff 37.77%
400.0mb: 63.10 vs 39.10 diff 38.03%
500.0mb: 50.50 vs 31.60 diff 37.43%
600.0mb: 42.30 vs 26.60 diff 37.12%
700.0mb: 36.50 vs 22.80 diff 37.53%
800.0mb: 31.90 vs 20.20 diff 36.68%
900.0mb: 28.80 vs 18.30 diff 36.46%
1.0gb: 25.60 vs 16.00 diff 37.50%
For files below 8kb fasthttp doesn't flush the headers which prevents sendfile from being used. That's why its still fast for small files. Around 1MB sendfile seems to be similar and with bigger files faster. So I would suggest increasing maxSmallFileSize to 1MB so we don't trigger sendfile below that size. @mehdipourfar (and anyone else) can you please test my benchmarks (preferable both the fasthttp and net/http ones) on your machines and share the results here so we can compare different machines and OSes? I want to use this research to also improve You can share the collapsed data like I did this way: |
|
Here is the result of first test on my laptop with 4 cores and 16gb ram: Ubuntu 20.04 size: sendfile vs r/w sendfile faster
1.0kb: 201.70 vs 28873.10 diff -14214.87%
2.0kb: 201.60 vs 25359.30 diff -12479.02%
3.0kb: 201.60 vs 27139.20 diff -13361.90%
4.0kb: 208.00 vs 22503.60 diff -10719.04%
5.0kb: 208.00 vs 21087.10 diff -10038.03%
6.0kb: 208.00 vs 23361.70 diff -11131.59%
7.0kb: 208.00 vs 21421.70 diff -10198.89%
8.0kb: 208.00 vs 22687.60 diff -10807.50%
9.0kb: 208.00 vs 22792.20 diff -10857.79%
10.0kb: 208.00 vs 23029.40 diff -10971.83%
20.0kb: 208.00 vs 21708.00 diff -10336.54%
30.0kb: 208.00 vs 19744.20 diff -9392.40%
40.0kb: 206.60 vs 18807.90 diff -9003.53%
50.0kb: 207.60 vs 17233.20 diff -8201.16%
60.0kb: 207.80 vs 17406.30 diff -8276.47%
66.0kb: 207.60 vs 16660.20 diff -7925.14%
66.0kb: 24920.20 vs 16635.70 diff 33.24%
70.0kb: 22243.40 vs 15635.30 diff 29.71%
80.0kb: 21614.10 vs 15023.90 diff 30.49%
90.0kb: 21686.40 vs 14596.90 diff 32.69%
100.0kb: 20765.80 vs 13763.50 diff 33.72%
200.0kb: 16100.60 vs 9952.40 diff 38.19%
300.0kb: 13088.80 vs 7651.70 diff 41.54%
400.0kb: 11112.10 vs 6365.70 diff 42.71%
500.0kb: 9550.60 vs 5385.80 diff 43.61%
600.0kb: 7871.00 vs 4683.30 diff 40.50%
700.0kb: 7375.90 vs 4102.30 diff 44.38%
800.0kb: 6549.90 vs 3450.60 diff 47.32%
900.0kb: 5842.20 vs 3293.20 diff 43.63%
1.0mb: 5354.20 vs 2878.20 diff 46.24%
1.1mb: 5317.00 vs 2715.30 diff 48.93%
1.2mb: 4716.50 vs 2576.70 diff 45.37%
1.5mb: 3906.00 vs 2056.10 diff 47.36%
2.0mb: 3150.60 vs 1593.30 diff 49.43%
2.5mb: 2438.20 vs 1305.90 diff 46.44%
3.0mb: 2085.90 vs 1060.10 diff 49.18%
100.0mb: 61.30 vs 36.60 diff 40.29%
200.0mb: 32.10 vs 19.20 diff 40.19%
300.0mb: 22.10 vs 12.80 diff 42.08%
400.0mb: 16.30 vs 9.60 diff 41.10%
500.0mb: 13.80 vs 9.60 diff 30.43%
600.0mb: 12.80 vs 6.40 diff 50.00%
700.0mb: 9.70 vs 6.40 diff 34.02%
800.0mb: 9.60 vs 6.40 diff 33.33%
900.0mb: 9.00 vs 6.40 diff 28.89%
1.0gb: 6.40 vs 6.40 diff 0.00%
|
|
And here is the results of the second test, again on my laptop. Ubuntu 20.04 (fasthttp test) size: sendfile vs r/w sendfile faster
1.0kb: 38730.00 vs 27537.20 diff 28.90%
2.0kb: 34115.40 vs 40646.70 diff -19.14%
3.0kb: 38447.20 vs 37626.60 diff 2.13%
4.0kb: 31612.70 vs 28817.00 diff 8.84%
5.0kb: 30252.60 vs 29768.90 diff 1.60%
6.0kb: 28384.00 vs 30855.30 diff -8.71%
7.0kb: 31220.70 vs 30460.40 diff 2.44%
8.0kb: 29656.10 vs 27386.60 diff 7.65%
9.0kb: 209.70 vs 15827.70 diff -7447.78%
10.0kb: 208.00 vs 19324.70 diff -9190.72%
20.0kb: 208.00 vs 17597.50 diff -8360.34%
30.0kb: 208.00 vs 17587.40 diff -8355.48%
40.0kb: 206.60 vs 13440.60 diff -6405.61%
50.0kb: 208.00 vs 14077.00 diff -6667.79%
60.0kb: 208.00 vs 11365.80 diff -5364.33%
66.0kb: 18790.60 vs 10890.70 diff 42.04%
66.0kb: 20969.50 vs 13451.00 diff 35.85%
70.0kb: 21698.90 vs 11246.70 diff 48.17%
80.0kb: 18075.50 vs 12162.70 diff 32.71%
90.0kb: 15109.10 vs 9559.70 diff 36.73%
100.0kb: 19645.30 vs 10843.80 diff 44.80%
200.0kb: 14048.00 vs 7265.30 diff 48.28%
300.0kb: 10745.50 vs 5901.60 diff 45.08%
400.0kb: 9267.10 vs 5828.80 diff 37.10%
500.0kb: 9165.90 vs 5197.60 diff 43.29%
600.0kb: 8828.50 vs 4509.20 diff 48.92%
700.0kb: 5860.70 vs 3214.50 diff 45.15%
800.0kb: 5274.10 vs 3534.10 diff 32.99%
900.0kb: 5477.90 vs 2991.90 diff 45.38%
1.0mb: 5231.90 vs 2313.30 diff 55.78%
1.1mb: 4487.40 vs 2546.60 diff 43.25%
1.2mb: 3466.70 vs 1867.10 diff 46.14%
1.5mb: 3189.00 vs 1645.40 diff 48.40%
2.0mb: 2613.60 vs 1284.60 diff 50.85%
2.5mb: 2055.10 vs 980.60 diff 52.28%
3.0mb: 1594.00 vs 842.90 diff 47.12%
100.0mb: 55.50 vs 28.70 diff 48.29%
200.0mb: 22.50 vs 14.50 diff 35.56%
300.0mb: 19.20 vs 9.60 diff 50.00%
400.0mb: 16.10 vs 9.60 diff 40.37%
500.0mb: 12.70 vs 9.60 diff 24.41%
600.0mb: 9.60 vs 6.40 diff 33.33%
700.0mb: 9.60 vs 6.40 diff 33.33%
800.0mb: 6.40 vs 6.40 diff 0.00%
900.0mb: 6.40 vs 6.40 diff 0.00%
1.0gb: 6.40 vs 3.20 diff 50.00%
|
Windows WSL2 Ubuntu 20.04 LTS size: sendfile vs r/w sendfile faster
1.0kb: 609.20 vs 33916.80 diff -5467.43%
2.0kb: 608.20 vs 34450.80 diff -5564.39%
3.0kb: 608.60 vs 34763.70 diff -5612.08%
4.0kb: 621.20 vs 32598.60 diff -5147.68%
5.0kb: 624.00 vs 32422.00 diff -5095.83%
6.0kb: 623.60 vs 32367.60 diff -5090.44%
7.0kb: 623.90 vs 32219.60 diff -5064.23%
8.0kb: 627.20 vs 32264.00 diff -5044.13%
9.0kb: 627.80 vs 32055.00 diff -5005.93%
10.0kb: 626.70 vs 31948.30 diff -4997.86%
20.0kb: 627.00 vs 31254.50 diff -4884.77%
30.0kb: 626.70 vs 29488.60 diff -4605.38%
40.0kb: 622.80 vs 28533.10 diff -4481.42%
50.0kb: 621.80 vs 28075.10 diff -4415.13%
60.0kb: 623.40 vs 27610.60 diff -4329.03%
66.0kb: 616.40 vs 26526.60 diff -4203.47%
66.0kb: 57604.20 vs 26513.60 diff 53.97%
70.0kb: 32767.80 vs 26187.20 diff 20.08%
80.0kb: 53517.30 vs 25757.00 diff 51.87%
90.0kb: 51916.60 vs 25380.00 diff 51.11%
100.0kb: 50409.20 vs 24211.30 diff 51.97%
200.0kb: 6139.00 vs 19525.10 diff -218.05%
300.0kb: 4600.30 vs 16430.80 diff -257.17%
400.0kb: 4437.60 vs 14219.40 diff -220.43%
500.0kb: 3467.50 vs 12369.80 diff -256.74%
600.0kb: 3954.60 vs 10962.40 diff -177.21%
700.0kb: 3155.80 vs 9857.20 diff -212.35%
800.0kb: 3411.60 vs 8888.70 diff -160.54%
900.0kb: 2822.10 vs 8066.90 diff -185.85%
1.0mb: 3167.40 vs 7374.50 diff -132.83%
1.1mb: 2570.30 vs 6830.20 diff -165.74%
1.2mb: 3043.60 vs 6313.90 diff -107.45%
1.5mb: 2477.10 vs 5161.70 diff -108.38%
2.0mb: 2384.60 vs 3935.60 diff -65.04%
2.5mb: 2761.90 vs 3182.10 diff -15.21%
3.0mb: 2441.40 vs 2659.50 diff -8.93%
100.0mb: 166.90 vs 82.70 diff 50.45%
200.0mb: 82.80 vs 41.60 diff 49.76%
300.0mb: 55.80 vs 28.70 diff 48.57%
400.0mb: 41.90 vs 22.00 diff 47.49%
500.0mb: 34.80 vs 17.40 diff 50.00%
600.0mb: 28.80 vs 15.50 diff 46.18%
700.0mb: 25.40 vs 12.90 diff 49.21%
800.0mb: 22.40 vs 12.40 diff 44.64%
900.0mb: 19.20 vs 9.60 diff 50.00%
1.0gb: 18.70 vs 9.60 diff 48.66%
|
|
I did some more research, it doesn't have to do with the file size it seems. Instead it has to do with keep-alive connections. The first sendfile on a new connection is always fast while followup sendfile calls on the same connection are always very slow. I made a Go issue about it: golang/go#45256 |
|
As discovered in the Go issue, this behavior only happens with both receiver and sender are sockets on the same machine. I think it is up to Go to fix this, not fasthttp. |
I have created a repository to show this.
fs-is-slow
The text was updated successfully, but these errors were encountered: