search

dokan-dev / dokan-dotnet

Dokan DotNet Wrapper
http://dokan-dev.github.io
MIT License
462 stars 116 forks source link

Right clicking file in Windows Explorer cause entire file to be "read" #268

Closed snakex64 closed 3 years ago

snakex64 commented 3 years ago

Hi!

I am assuming there is something wrong either with my code or in Dokan. When I right click a file in the Windows Explorer, it freeze until the entire file has be "read", I can see the "ReadFile" method called repeatedly. For big files it can freeze for quite a while before the right click menu opens.

Is there a way to go around this ?

Thanks,

Liryna commented 3 years ago

Hi @pascx64 ,

If I remember normally only a part of the file should be read in that case. Have you look if you get the same behaviour with the mirror C sample ? You can also use procmon to see if the same ReadFile happens on NTFS.

snakex64 commented 3 years ago

Hi @Liryna ! Thanks for the very fast reply,

I does seems like it behave the same with the Dokan-dotnet mirror sample. Except it freeze for a fraction of the time since the file is local, still freeze for a good 1-2s for a 1gb executable. The issue seems to only be with executables.

As for the mirror C sample, it is hard to say. it is definitely slower to right click on an executable versus a normal file but less slow than with dokan-dotnet.

It is also notable that in a normal folder ( outside of dokan ), right clicking on an executable is near-instantaneous, like it is when I right click on a normal file in dokan.

Liryna commented 3 years ago

@pascx64 Please try with procmon and compare the type of read like offset and size.

For information, it is explorer in that case that create those reads or another app. Dokan is only getting them and forward them to the user filesystem. If it is the exact same read that on NTFS (by looking at procmon logs), will need to see what is making it slow.

snakex64 commented 3 years ago

I think the reads are still there even directly in the file explorer outside Dokan. It's just that it's slowly ( and therefor visible ) with Dokan-dotnet mirror sample. And since my program is accessing everything remotely it's very slow

Liryna commented 3 years ago

@pascx64 This is expected in that case. You would need a caching that would help to fastly reply to explorer. Lik reading a head of the file at first read-.