Server analysis is buggy

The server analysis doesn't work so well anymore:

1. In 4/5 cases, the spinner never stops, even when the analysis is finished. The only way to get rid of that is a page reload, but then the analysis is often gone completely, and you can't re-request it. The button now is just reloading the page again.

2. In endgames and very tactical positions the analysis is just broken. For example it says "Checkmate is now unavoidable" when the position is already a mate in x moves. And sometimes it recommends a losing move! Here is an example:



On 22.f4 it says I should have played Qa5 … which gives Black a mate in 7. My move was also bad, but better than Qa5. :) The only move that keeps me alive is actually f3. This should never happen, and I don't understand how the engine can miss that.

So please increase the analysis depth beyond 40 or so. Currently it seems to be on depth 10 or lower, because after that it sees that Qa5 is losing on the spot.
Thank you!

Looks like it takes Stockfish until depth 21 or 22 in that position until it sees Qa5 gets mated. The reality is that with millions of positions analyzed every day, it's not economical to spend more than a few seconds on each position.

Better to shift your perspective and understand that engines are fallible. In order to reach high depths, they have to aggressively prune moves, which means that they can and do miss things. If you want to find the truth of a position, you'll need to spend some time and computing power digging into the details.

(And to be fair to Stockfish, all moves in that position lose completely, so it's not like it was a game-changing misjudgment - probably it was looking down lines it thought might give it a way out rather than spending time on a move it already knew was losing.)

I would be nice to have option to provide own CPU in browser to analyze game, with default parameters as lichess server side is using with option to deepen analysis. Especially on imported games, have that option to re-evaluate deeper.