Re: UBIFS vs Logfs (was [RFC PATCH] UBIFS - new flash file system)

[Artem Bityutskiy]

Willy Tarreau wrote:
> > Well, even auto-levelling storage should benefit from a filesystem which 
> > minimizes the total number of flash sectors churned, which means doing 
> > as few writes as possible and to large, contiguous sections.
>
> Exactly. At exosec, we ship one appliance which writes statistics to a
> partition on a compactflash every 5 minutes. We preferred to go with JFFS2
> exactly because of this reason. We never had any problem proceeding this way.
> I'm not sure if it would have been the same with ext2 though.

Yes, as I agreed in a previous mail this may make sense in some cases.

But in general it is not a good approach. Basically, it is wastage of resources.
Indeed, first the firmware on MMC/SD/etc makes efforts to make flash look
like a block device. It gives you in-place updates, but by cost of performance
and reliability. Then you just drop this nice property, and use JFFS2, which
assumes it has only out-of-place updates. But if this solves the task you have
- fine!

--
Best Regards,
Artem Bityutskiy (ÐÑÑÑÐ ÐÐÑÑÑÐÐÐ)
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