EXT4 Getting Faster Case-Insensitive Performance

[phoronix]

Phoronix: EXT4 Getting Faster Case-Insensitive Performance

The Linux 5.2 kernel brings optional per-directory case-insensitive filenames/folders while with the Linux 5.3 kernel that new EXT4 feature will see better performance...

http://www.phoronix.com/scan.php?pag...nsitive-Faster

[anarki2]

I really wish they made this a mount option for the whole FS.

[DoMiNeLa10]

I really wish they made this a mount option for the whole FS.

Since this is an attribute, you might be able to set it on the root directory of the file system. If that isn't the case, you can just do that for every directory in root.

[milkylainen]

Going Windows. Such an insensitive clod...

[Etherman]

Does this really belong in the kernel?

[xfcemint]

Does this really belong in the kernel?

Open file operation must be able to search for a file name case-insensitive.

Open-file operation is part of any filesystem driver, which is part of the (monolithic) Linux kernel. In micro-kernels, FS is a driver, but not in the kernel.

[microcode]

Technically if people were willing to modify their software, sure, it probably should not belong there. Adobe Photoshop for macOS still doesn't work if you turn on case-sensitive filenames, AFAIK.

[xfcemint]

Technically if people were willing to modify their software, sure, it probably should not belong there. Adobe Photoshop for macOS still doesn't work if you turn on case-sensitive filenames, AFAIK.

Nope;

case insensitive file-open cannot be provided by applications.

If an application wants to open "myAppSettings.dat", how can it know that the file "MyAPPseTTings.DAT" exists? Only the file system driver can do the case-insensitive search of particular directorie's file name list.

[milkylainen]

Nope;

case insensitive file-open cannot be provided by applications.

If an application wants to open "myAppSettings.dat", how can it know that the file "MyAPPseTTings.DAT" exists? Only the file system driver can do the case-insensitive search of particular directorie's file name list.

Umm.. No?
You can put it in an application. You list all entries in a path and do a case insensitive search for a file name before you open it.
It's absolutely trivial. You know, there are even handy ages old posix functions for you. strcase*
It's exactly what the kernel will have to do if you do a camelcase name open in a case insensitive mountpoint.

Every application can do it's own case insensitive file search.
But of course that's stupid and pointless. Also not uniform. And that's why it resides in the kernel.

[xfcemint]

Umm.. No?
There is no difference. You list all entries in a path and do a case insensitive search for a file name before you open it.
You know, there are even handy ages old posix functions for you. strcase*
It's exactly what the kernel will have to do if you do a camelcase name open in a case insensitive mountpoint.

While it appears that it woud be possible for application to do case-insensitive file open by requesting a kernel to provide a list of ALL files in a directory, this is an extremely bad idea.

I don't want to go into details.

FS driver should open files by file name. There are methods to make this operation fast and efficient of FS driver level (like search trees or hashing). On application level, it turns into a complete disaster.