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"Computer analysis" (fishnet) is weaker compared to local

#1
imgur.com/a/59peJhj

The "computer analysis" sometime give poor results. In attached image, CA says that "Qc5" is the best move, but local analyse shows mate in 15 and "Qc5" is not even the second best move.

I understand that "fishnet" results may slightly differ, but missing mate make other CA suggestions dubious.

Is this a bug or expected behaviour?
#2
gonna let others chime in, but of course when you're at depth 29 you're going to be deeper than whatever server analysis you've received (lichess is not going to analyze each move at depth 29, far from that). Also "missing mate" is quite a stretch when talking about mate in 15.

Basically all this means is that Qc5+ was the best move at whatever depth the server analysis reached for that move, which was certainly a reasonable depth (even if it's not 29 plies/14.5 moves).
#3
You are right and I won't even bother about mate in 25, but 15 looks like reasonable depth which should be found by CA.

This is not the first time "local analyse" give different results from CA for me. The question I'm asking -- is this expected behaviour?
#4
yes it is expected behavior. you let your local analysis get to depth 29, which is way deeper than any server analysis will give you (in an unknown complex position) because it takes time and hardware resources to reach depth 29.
#6
"Basically all this means is that Qc5+ was the best move at whatever depth the server analysis reached for that move, which was certainly a reasonable depth (even if it's not 29 plies/14.5 moves)."

fishnet does not use x depth for precisions it gives a node quota for all games and then decides which moves get more of the quota for analysis this can lead to the horizon effect which is what happened above
#8
I still think that something is wrong with CA. For example, this party move 21.



CA shows -9.5, any local analyse (even Stockfish 11 on minimum settings) finds mate in 5.

imgur.com/a/ZaOQzJT
#9
@Maradon1977 its the horizon problem you can only see as far as the horizon until you move server analysis does not go to x depth but rather to x node which leads to this but increasing node count would be alot more strain on the network