[haiku-development] Re: ext3 Journal WIP patch

  • From: Janito Ferreira Filho <jvffprog@xxxxxxxxxxx>
  • To: Haiku Development <haiku-development@xxxxxxxxxxxxx>
  • Date: Fri, 16 Apr 2010 18:28:00 +0000

> korli@xxxxxxxxxxxxxxxx wrote:
> 
> Hi Janito,
> 
> Here are a few comments:

Hi,

thanks for your comments =). 

> * Journal structs probably need a _PACKED attribute.

I'll add the _PACKED attribute to the appropriate structures. BTW, could you 
give a brief explanation on what it changes (or in what it restricts the 
compiler)?

> * The journal should care if the volume is mounted read only or 
not.

I currently haven't implemented this checking because (at this stage) I'm 
assuming it's read-only. Either way, I think it wouldn't be too hard to 
implement. Would you suggest the Journal class having it's own set of flags set 
up during initialization or should it read these flags from the volume?

> * I'm not sure it's useful at first to support having the 
journal on a
> different volume.

I could think of enterprise scenarios, but nothing really interesting for the 
desktop. Either way, if ext3 supports it, I think it would be nice to at least 
pave the way for future support, as long as it doesn't hurt the implementation 
=). Do you agree?

> BTW I'm 
wondering if it would be preferable to share some journal code with BFS.

I'll try to base off the BFS Journal code. I'm currently using it for 
inspiration, but I think there are many situations where they handle things 
differently (consider for example log replaying). Once we get to Transactions 
and more general operations, there might be more opportunities to share code. 
It would be wise to foresee where the crossing points will be, but I haven't 
thought about any yet =(. Do you suggest any?

I hope I can implement a design that fits nicely in Haiku =). Again thanks for 
your answers!

Janito

                                          
_________________________________________________________________
Hotmail: Free, trusted and rich email service.
https://signup.live.com/signup.aspx?id=60969

Other related posts: