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Interview With Reiser4 Author Hans Reiser
An anonymous reader writes "KernelTrap has an interesting interview with Hans Reiser, the author of two revolutionary Linux filesystems, Reiser3 and Reiser4. Reiser3 was the first journaling Linux filesystem. Reiser4 is a complete rewrite that is claimed to offer amazing performance and a new plugin architecture offering semantic enhancements to rival Microsoft's WinFS and Apple's Spotlight. Comparing Reiser4 to WinFS, Reiser says in the interview, "Reiser4 is a much more mature design, representing a 10 year effort"."
Here's a link to the page that hides the asshats making the pages super-wide with lame comments.
This one is pretty old review back when Reiser4 was still Experimental. More recent one would be here, but it too is over a year old.
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Anything more specific? I'm the first to admit that he can be rather immature, spoiled and inflammatory but a quick look at the link you offered showed none of these attitudes. Actually the discussion sounded quite civilized, so what's the problem?
Don't think of it as a flame---it's more like an argument that does 3d6 fire damage
There's a beta version available to developers now. There was a lot of criticism of it when it was first unveiled so they went back to the drawing board and released a new version that claims to address those concerns.
This is my sig.
XFS beta came out 9/22/2000 (its source code was first publically available on 3/30/2000) The first journaling version of reiserFS was release in november of 1999.
JFS came later than XFS though I can't find the date.
Of course officially ext3 came out before reiserFS in september of 1999, though ext3 is the real winner. Which produced workable code first I have no idea.
My understanding is that the kernel developers have pointed out flaws in the benchmarks and he has accepted the criticisms but points out that they are just benchmarks and all benchmarks have flaws. This would not be a problem if he didn't keep referring to the benchmarks when trying to ram a change into the kernel. You can't have it both ways.
It's also my understanding that the key reason kernel developers don't want to accept his patches is that they don't like big megapatches that affect many systems or replicate functionality that is already in the kernel -- it's bad for maintenance. It's also my understanding that he doesn't want to break up the patches himself and he has refused help from others who are eager to do it for him. For him, it's an all or nothing deal -- take it or leave it. The kernel developers say "fine, we'll leave it", but he doesn't accept their decision and continues to complain. Again, you can't have it both ways.
Reiser may be a genius, but even geniuses have to (*gasp*) live in the real world and negotiate with real people. Even if Reiser is smarter than all the kernel developers (doubtful), it pays to treat your so-called "inferiors" with respect. Even janitors and garbage collectors can have wisdom that we don't have and things they can teach us.
This is a type of question that, unfortunately, cannot be answered correctly. Well, it can: it depends. But that's not what you are after. As Hans himself pointed out, there are some fsync performance problems with ReiserFS. If you look at PostgreSQL config files, you'll notice a "fsync" setting, and if you look at pgsql-performance mailing list, you'll see frequent mentions of fsync. Obviously, fsync affects DBs (not just PostgreSQL), and ReiserFS may not currently be so great for DBs. However, it is apparently good for large directories (1 directory, lots of files in it). So, it depends how you use your FS.
Describe how you use your FS, and maybe somebody can provide good feedback.
Simpy
Are you sure you understand what ReiserFS is suppose to do? What about WinFS? I don't think compairing WinFS to ReisierFS is quite like compairing Qt to Explorer. The functionality of WinFS is (as I understand things) a proper subset of the functionality of ReiserFS.
Again, there purposes are not really different. Sure, ReiserFS is a full blown filesystem, and WinFS is not a filesystem, however the functionality of WinFS is included in ReiserFS. The fact that they operate at different levels is the reason for Reiser's remarks concerning ReiserFS and WinFS. That's his point. WinFS works on a user level to provide functionality that ReiserFS provides at the filesystem level, and Reiser feels that this is a more mature design.
...interesting if true.
I never said the above words attributed to "Rieser".
I am sure of it becuase I would absolutely never say that "Linux kernel developers do what's right because it is _right_, not because somebody else does it.".
I am just not that nice a guy that I would say such a thing.:-/ I am guilty of saying the opposite at various times. I am known for this, and not particularly liked for it.:-)
This is a forged quote. Note the false defensiveness put into it in the sentence "So there's really no point in trying to push your agenda by trying to scare people with MS activities." That really sounds like someone at MS posted this.
It does not matter so deeply that MS put it into or out of the kernel, what matters is how they layered the code relative to itself --- that is, do they use the FS API, which lacks an insert or excise operation, to repack small objects that they squished together within a file, and does that layering make things slow. I think it almost certainly does make it slow, and it definitely is inelegant.
Hans Reiser
Reiser4 Architect
Namesys
Sorry, but ReiserFS v4 is a tiny subset of WinFS. I would say that the grandparents analogy is apt.
To clarify: ReiserFS adopts database concepts in two ways. It uses a B-tree variation to allow efficient hierarchical storage layout and it uses it to allow single-process atomicity. That is all.
WinFS on the other hand is an actual factual relational database (actually parts of MS SQL-Server) built on top of NTFS; a NTFS file is a special datatype among many others. One can specify relations and constraints as one would in a relational database. It has full atomicity (ACID), whereas ReiserFS's atomicity just gives a rollback local to a process. That is, any read or write may be transactionally inconsistent if there is more than one process dealing with the data whereas in WinFS one gets full support for transactions.
In addition to the above WinFS of course provides the obvious big end-user features; Fast queries over all the data in a relational way, and triggers that allow actions performed when data is changed or queried (both of which OSX provides in a slightly more ad-hoc way on the side).
So where does ReiserFS fit in? Well, the complaint that Hans Reiser has against WinFS is that not everything is a file, rather files is a special case mapping down to NTFS streams. Small auxilliary data is handled by other data-types in an SQL-like manner in WinFS, which to me at least seems like a quite sane approach. ReiserFS instead just optimizes the heck out of small files, planning to just take the UNIX principle to the limit, everything is a file, even if you just want to store a small integer. This makes everything fit into the classic filesystem namespace in a good way, but it is really less structured than the WinFS approach. WinFS relates whereas ReiserFS just provides really fast unstructured primitives.
Overall I don't expect ReiserFS to be overly relevant to the OSS answer to WinFS, mostly because I don't really expect a OSS answer to WinFS on that level. While Microsofts approach is a great piece of engineering is is also a huge amount of work. More likely is that the Apple approach will continue to be the important one; Just add the stuff needed to get the actually important end-user features today, work on the low-level programmer features later.
On the other hand ReiserFS v4 really appears to be very very fast. No doubt great features can be built on top of it, but on the other hand the classic VFS abstraction is a good thing. Swapping filesystems without impacting the userland is a feature that is really useful, so it seems fairly likely that the simpler approaches like Beagle will get to add the basic end-user features instead of fattening up the file systems (I highly disagree with Reiser that it is on the actual FS-level things should happen in the future). People who need databases can, *gasp*, use a database instead.
In fact, I am suprised to not yet have seen systems like Gnome and KDE fire up a stripped down PostgreSQL process or something similar to provide applications with an excellent database for whatever their needs might be. For Microsoft doing a thing like that hurts the bottom line (they do charge a fair bit of money for SQL-Server after all), but there is no reason why an OSS platform should not utilize the best technology it has available at every turn.
Oh well, getting off track. Summary: ReiserFS v4 is a tiny subset of WinFS feature-wise, it just does it very very fast.