why is this project so much faster?

[hiqbn]

https://github.com/VictoriaMetrics/fastcache

can port over the ideas to freecache? it doesn't have expiry controls

[recoilme]

I do small tests (just for my small project - https://github.com/recoilme/pudgedb)
With https://github.com/antirez/mc-benchmark

May be i do something wrong, not sure. But i see what fastcache has bad latency all time
fastcache:

./mc-benchmark -h 127.0.0.1 -p 11211 -c 200 -n 10000 -k 1
====== SET ======
  10046 requests completed in 0.22 seconds
  200 parallel clients
  3 bytes payload
  keep alive: 1

0.31% <= 0 milliseconds
17.23% <= 1 milliseconds
56.60% <= 2 milliseconds
75.81% <= 3 milliseconds
89.07% <= 4 milliseconds
93.84% <= 5 milliseconds
96.74% <= 6 milliseconds
97.62% <= 7 milliseconds
98.06% <= 8 milliseconds
98.34% <= 9 milliseconds
98.54% <= 10 milliseconds
98.65% <= 11 milliseconds
98.71% <= 12 milliseconds
98.74% <= 13 milliseconds
98.75% <= 14 milliseconds
98.90% <= 15 milliseconds
98.91% <= 16 milliseconds
98.91% <= 17 milliseconds
98.92% <= 26 milliseconds
98.93% <= 29 milliseconds
98.94% <= 32 milliseconds
98.95% <= 33 milliseconds
98.96% <= 35 milliseconds
98.97% <= 41 milliseconds
98.98% <= 44 milliseconds
99.00% <= 47 milliseconds
99.01% <= 49 milliseconds
99.04% <= 51 milliseconds
99.05% <= 53 milliseconds
99.06% <= 57 milliseconds
99.07% <= 60 milliseconds
99.09% <= 63 milliseconds
99.10% <= 64 milliseconds
99.11% <= 69 milliseconds
99.12% <= 77 milliseconds
99.13% <= 81 milliseconds
99.15% <= 85 milliseconds
99.16% <= 89 milliseconds
99.17% <= 91 milliseconds
99.18% <= 93 milliseconds
99.19% <= 96 milliseconds
99.20% <= 97 milliseconds
99.21% <= 98 milliseconds
99.22% <= 103 milliseconds
99.23% <= 104 milliseconds
99.24% <= 106 milliseconds
99.26% <= 108 milliseconds
99.27% <= 111 milliseconds
99.28% <= 112 milliseconds
99.29% <= 117 milliseconds
99.31% <= 121 milliseconds
99.32% <= 123 milliseconds
99.33% <= 127 milliseconds
99.34% <= 130 milliseconds
99.35% <= 132 milliseconds
99.36% <= 136 milliseconds
99.37% <= 137 milliseconds
99.38% <= 141 milliseconds
99.39% <= 146 milliseconds
99.40% <= 149 milliseconds
99.41% <= 154 milliseconds
99.42% <= 155 milliseconds
99.43% <= 159 milliseconds
99.44% <= 160 milliseconds
99.45% <= 161 milliseconds
99.46% <= 162 milliseconds
99.47% <= 164 milliseconds
99.48% <= 166 milliseconds
99.49% <= 170 milliseconds
99.50% <= 172 milliseconds
99.52% <= 175 milliseconds
99.53% <= 178 milliseconds
99.54% <= 182 milliseconds
99.55% <= 184 milliseconds
99.57% <= 190 milliseconds
99.60% <= 191 milliseconds
99.61% <= 192 milliseconds
99.65% <= 193 milliseconds
99.69% <= 194 milliseconds
99.70% <= 195 milliseconds
99.75% <= 196 milliseconds
99.77% <= 198 milliseconds
99.80% <= 199 milliseconds
99.85% <= 200 milliseconds
99.86% <= 202 milliseconds
99.87% <= 203 milliseconds
99.91% <= 204 milliseconds
99.92% <= 205 milliseconds
99.99% <= 206 milliseconds
100.00% <= 207 milliseconds
44848.21 requests per second

====== GET ======
  10052 requests completed in 0.25 seconds
  200 parallel clients
  3 bytes payload
  keep alive: 1

0.02% <= 1 milliseconds
0.58% <= 2 milliseconds
9.00% <= 3 milliseconds
58.55% <= 4 milliseconds
87.29% <= 5 milliseconds
92.40% <= 6 milliseconds
95.58% <= 7 milliseconds
96.52% <= 8 milliseconds
97.40% <= 9 milliseconds
98.01% <= 10 milliseconds
98.60% <= 11 milliseconds
98.68% <= 12 milliseconds
98.74% <= 13 milliseconds
98.79% <= 14 milliseconds
99.25% <= 15 milliseconds
99.27% <= 16 milliseconds
99.28% <= 17 milliseconds
99.29% <= 18 milliseconds
99.35% <= 19 milliseconds
99.36% <= 20 milliseconds
99.37% <= 22 milliseconds
99.38% <= 23 milliseconds
99.42% <= 24 milliseconds
99.44% <= 26 milliseconds
99.51% <= 27 milliseconds
99.60% <= 28 milliseconds
99.67% <= 29 milliseconds
99.70% <= 30 milliseconds
99.73% <= 38 milliseconds
100.00% <= 39 milliseconds
39888.89 requests per second

freecache

./mc-benchmark -h 127.0.0.1 -p 11211 -c 200 -n 10000 -k 1
====== SET ======
  10094 requests completed in 0.20 seconds
  200 parallel clients
  3 bytes payload
  keep alive: 1

5.85% <= 1 milliseconds
39.81% <= 2 milliseconds
63.44% <= 3 milliseconds
77.00% <= 4 milliseconds
83.16% <= 5 milliseconds
88.18% <= 6 milliseconds
92.38% <= 7 milliseconds
95.69% <= 8 milliseconds
97.70% <= 9 milliseconds
99.06% <= 10 milliseconds
99.31% <= 11 milliseconds
99.72% <= 12 milliseconds
99.94% <= 13 milliseconds
100.00% <= 14 milliseconds
50723.62 requests per second

====== GET ======
  10016 requests completed in 0.23 seconds
  200 parallel clients
  3 bytes payload
  keep alive: 1

0.43% <= 2 milliseconds
12.77% <= 3 milliseconds
76.28% <= 4 milliseconds
88.96% <= 5 milliseconds
94.17% <= 6 milliseconds
97.50% <= 7 milliseconds
99.31% <= 8 milliseconds
100.00% <= 9 milliseconds
42803.42 requests per second

Testgist https://gist.github.com/recoilme/a15e511084c3662ce3982a88bf4fd153