The New Windows Subsystem for Linux (WSL2) Architecture [video]

Post by billziss » Fri, May 10, 2019, 1:15 AM UTC

dragonwriter wrote: post #100

billziss wrote: post #71

Although many people seem to be receiving the WSL2 news well, I am one of the few that feels that we will be missing something important with this new direction. WSL1 was pushing the boundaries of OS research: - a method for having multiple syscall interfaces in a mainstream OS - processes in WSL1 were real NT processes (even if lacking some of the NTOS environment) - direct integration with the rest of the OS withou…

> Finally WSL2 will be distributed with Windows which raises some licensing questions (IANAL) if not in the letter of the GPL license at least in spirit. I write GPL'ed software myself and I would be somewhat miffed if I saw my software used in a similar manner (i.e. "via a VM", but still distributed with non-GPL code). Mere aggregation of non-GPL code with (“distributed with”) GPL code expressly is consistent with t…

Post by dragonwriter » Fri, May 10, 2019, 2:58 AM UTC

schwede wrote: post #99

billziss wrote: post #71

Although many people seem to be receiving the WSL2 news well, I am one of the few that feels that we will be missing something important with this new direction. WSL1 was pushing the boundaries of OS research: - a method for having multiple syscall interfaces in a mainstream OS - processes in WSL1 were real NT processes (even if lacking some of the NTOS environment) - direct integration with the rest of the OS withou…

I agree that WSL1 was a fascinating project. It’s too bad all that work has gone to waste.

Post by nikbackm » Fri, May 10, 2019, 7:17 AM UTC

billziss wrote: post #93

mey wrote: post #90

Earlier quoted context omitted.

As described in the Video, they could not keep up with feature parity of syscalls in Linux and some concepts are simply incompatible with the two systems. They reference the concept of open file handles and moving folder structures. I think they found the boundary of OS research in this case, and a better product is using the actual Linux kernel.

> They reference the concept of open file handles and moving folder structures. I think this comment may have been disingenuous on their part. The reason is that this problem more than likely still exists in WSL2 for the /mnt/c, /mnt/d file systems (i.e. what they used to call "DrvFs" in WSL1). WSL1 comes with (at least) 2 file systems. "VolFs" which is the file system that they use for the Linux root file system and…

Post by nikbackm » Fri, May 10, 2019, 7:24 AM UTC

wnevets wrote: post #89

resters wrote: post #62

Earlier quoted context omitted.

why is that? performance?

The last time I checked virtualbox and hyper v can't run at the sametime.

Post by billziss » Fri, May 10, 2019, 4:44 PM UTC

nikbackm wrote: post #105

billziss wrote: post #93

Earlier quoted context omitted.

> They reference the concept of open file handles and moving folder structures. I think this comment may have been disingenuous on their part. The reason is that this problem more than likely still exists in WSL2 for the /mnt/c, /mnt/d file systems (i.e. what they used to call "DrvFs" in WSL1). WSL1 comes with (at least) 2 file systems. "VolFs" which is the file system that they use for the Linux root file system and…

> My contention is that they could have instead replaced VolFs with a native WSL1 file system that uses a disk partition or VHD as its backend storage, thus eliminating the Windows I/O stack in the same way. They could then have implemented proper Linux file system semantics without any baggage. But that would require them to implement a new file system from scratch wouldn't it? VolFs in WSL1 relied on NTFS to do the…