Re: reiserfs panic with kernel 2.6.19

2006-12-26 Thread Joachim Wagner
Thanks for looking into this Vladimir!

 reiserfs panic labeled PAP-5680 which you encountered indicates that file
 truncate did not complete. Actually, reiserfs does not have to panic, it
 has to return EIO or something suitable.
Indeed, that would be much better behaviour. Maybe the attached patch is okay. 
It compiles fine with 2.6.19.1. However, I don't see how to test it. 

 Could it be hardware fault?
In case you saw the smartd warnings concerning /dev/hda, the reiserfs panic 
occurred with a reiserfs on an S-ATA software raid 5 (/dev/sd[a-g]1) I got a 
few months ago. The P-ATA boot disk is the only old component. I don't 
remember any worrying S-ATA or raid messages in my syslog. Unfortunately, I 
cannot have a closer look at the moment as I'm away on holiday.

Regards,
Joachim
--- stree.orig	2006-12-11 20:32:53.0 +0100
+++ stree.c	2006-12-26 14:53:48.0 +0100
@@ -1898,9 +1898,30 @@
 goto out;
 			reiserfs_update_inode_transaction(p_s_inode);
 		}
-	} while (n_file_size  ROUND_UP(n_new_file_size) 
-		 search_for_position_by_key(p_s_inode-i_sb, s_item_key,
-	s_search_path) == POSITION_FOUND);
+	if (n_file_size  ROUND_UP(n_new_file_size)) {
+		retval = search_for_position_by_key(p_s_inode-i_sb,
+		  s_item_key, s_search_path);
+		if (retval == IO_ERROR) {
+			reiserfs_warning(p_s_inode-i_sb,
+ 	jw-5670: reiserfs_do_truncate: 
+ 	i/o failure occurred searching for %K,
+ 	s_item_key);
+			err = -EIO;
+			goto out;
+		}
+		if (retval == FILE_NOT_FOUND) {
+			reiserfs_warning(p_s_inode-i_sb,
+ 	jw-5672: reiserfs_do_truncate: 
+ 	file not found searching for %K,
+ 	s_item_key);
+			err = -EIO;
+			goto out;
+		}
+	}
+	else
+		retval = POSITION_NOT_FOUND;
+
+	} while (retval == POSITION_FOUND);
 
 	RFALSE(n_file_size  ROUND_UP(n_new_file_size),
 	   PAP-5680: truncate did not finish: new_file_size %Ld, current %Ld, oid %d,


Re: Hans selling Namesys

2006-12-26 Thread Quinn Harris
All of the Reiser4 code as it exists today will always be available under GPL 
no matter who buys the copyright.  The only reason I can see to buy Namesys 
is either to offer or use a re-licensed copy of the code or to take advantage 
of the knowledge of the current Namesys employees.  There might be some value 
in existing contracts with DARPA or whoever but I am not sure.

The re-license thing could be very difficult if there are many people who 
decide on if it will be re-licensed.  This is why Hans has always retained 
exclusive copyright to all the code.  I would question if re-licensing would 
be feasible with any structure that could be called community ownership.

In the short term I believe the current employees of Namesys (how many are 
there now?) are the most valuable asset.  It takes time to become acclimated 
to such a complex piece of code.  Having to rehire a new set of people would 
easily set the work back by a few months to a year.

On the other hand, I also believe that exclusive rights to the code could be 
very valuable to companies like Apple or even everybodies favorite, 
Microsoft.

Even with knowledge of the mechanisms Reiser4 uses, I expect it could cost 
another company over a million dollars more to completely re-implement a 
similar file system compared to having uninhibited use of the existing code.

I could see a company like Apple using a file system like Reiser4 to improve 
the performance of the existing file system and more importantly to enable 
acceptable performance for a namespace the unifies the file system and XML 
(chosen because of its widespread use) allowing for the elimination of 
the save file paradigm.  Basically, applications could store data in an in 
memory XML DOM (as I expect Open Office does today) which would be seamlessly 
written to disk after each transaction on that DOM.  (Reiser4 can do this 
much better than any other FS because of efficient storage of small items and 
the reiser syscall if ever finished).  Such a system could claim, Never 
loose data, Ever.  (This is what databases have been doing for decades.)  
Actually you could probably loose a few seconds of data as I expect flushing 
to disk after each character typed wouldn't be acceptable.  Though even this 
problem could be eliminated with an small NVRAM, Flash and HD hybrid.  

Wrap the NVRAM and flash in hard casing, mix in a good real time internet 
backup scheme (plugins and efficient extensible metadata would help here), 
and it would become possible to insure against data loss at a reasonable 
cost.  Something like, with this laptop and OS, if you loose any data, even 
if you drop it off a 20 story building 1 second after typing that last word, 
we will cut you a check for $100,000.  Some limitations apply.  I think many 
would pay an extra few hundred dollars for something like that.

Of course, getting to that place would require alot of further work but 
Reiser4 would be a good start.

I would rather see this under GPL in Linux but this verbage was to elaborate 
on one reason that the existing code would be worth a substantial chunk of 
change.  This could also be a reason why it would be in the interest of 
existing Linux companies to ensure development continues.

Bottom line, Han's best hope at making any significant amount on this sale 
would rest in a company seeing the value in Reiser4 wishing to re-license the 
code.


On Monday 25 December 2006 4:22 pm, [EMAIL PROTECTED] wrote:
 I'm an offer to buy some or little part of the legal properties of
 Namesys, still compromised with open source community.

 How much it costs at all?

 I work with reiser4 in my own enterprise private distribution and want
 this project lasting for a long time.

 André Zaiats.
 Codix - São Paulo - Brazil

  Hello,
  from reading all this stuff it seems to look like a competitors
  intrigue. But we don't have any evidences upon this neither do
  we have a sentence, yet...
 
  Can we build up a ReiserFS-community based fund to buy or save
  Namesys over time to help continue the current development? Just
  an idea.
 
   From my point of view the there are three general alternatives:
  * let/help someone really interested to buy Namesys
  * increase Hans' financial input directly to help himReiserFS
  * ReiserFS34 get bought by someone and become commercial or
 will vanish at once
 
  As I followed ReiserFS since 1997(?+-) but really don't know
  enough about the current case I'm not sure with my priorities in
  the list above.
 
  Best wishes to all contributors,
  my best wishes for your Xmas!
 
  Manuel
 
  Joe Feise wrote on '06-12-25 20:55:
  http://www.wired.com/news/technology/0,72342-0.html