3 ms·
What do you call by "queue depth". Is it the number of concurrent clients? If it's true then it looks very suspicious that avg. latency decreases as the number
by rystsov 10y ago
What do you call by "queue depth". Is it the number of concurrent clients?
If it's true then it looks very suspicious that avg. latency decreases as the number of concurrent clients goes up. How do you measure avg. latency?
Let me illustrate what the avg. latency usually means.
Imagine that we have two concurrent users: Alice and Bob. During the testing lasting one second, Alice managed to send 3 requests per second, the first request took 0.5 seconds while the rest were executed in a quarter of a second each. In the same time, Bob did only 2 requests, each of them took 0.5 seconds.
So the average latency is the sum of execution time taken by each request divided by the number of all requests, in our case it's (0.5+0.25+0.25+0.5+0.5) / 5 = 0.4
Did you use the same definition?
- mhf8o9a 10y agoLatency does increase with concurrency. Latency decreases with the number of keys, as long as they are less than the concurrency. If the number of keys is more than the concurrency, there is no additional benefit and latency remains flat.
- rystsov 10y agoThanks, I didn't notice that the clients operate over the same key set, so I didn't think about the contention. It makes sense.