Can anyone reproduce this bug?

[GJones]

When copying large amounts of data (in my case, a 1 GB file) from a USB stick to the hard drive...

- Copying to an ext4 filesystem: lag galore. Cursor freezes, applications freeze, everything is unresponsive until the transfer is finished.

- Copying to an XFS filesystem: no lag whatsoever. System remains completely responsive while copying the file(s).

I'm starting to wonder if some of the performance issues I've seen on Linux stem from using ext4. Has anyone else seen this issue? Are there any mount flags for ext4 that could help, e.g. maybe turning off delayed allocation?

[gapan]

I can only say that I have never really used ext4 on a daily basis, I've been using xfs for years now and I've never had such problems...

[witek]

I also stay with XFS, at least for large partitions to hold my data. But I observed the same: cursor freezes, applications freeze, everything is unresponsive when I copied big files from USB stick to NTFS partition. Apparently ntfs-3d driver was to blame.

[thenktor]

No problems here with any Linux file systems.

Apparently ntfs-3d driver was to blame.

ntfs-3g is a mess when it comes to CPU usage. One of the reasons I'm using Linux file systems on all my USB sticks, too. Who cares about Windows users?

[GJones]

Yes, this does in fact seem to involve delayed allocation. With delalloc, my laptop lags like mad when copying a 1 GB file from the home partition to the root partition. With nodelalloc, it performs as I'd expect it to, i.e. things take longer but graphical applications do not lag.

[JRD]

No problem and no lag to copy from USB to a internal ext4 partition here.