Re: [ECOS] Stress testing JFFS2

[David Vrabel <dvrabel at arcom dot com>]

Hi,

[Note: It's been ages and ages since I did any real work with JFFS]

> 20-30k ram seems excessive for 16 files.

In your test you wrote about 800 files so that's 30000/800 ~ 40 byte per 
written file.  Doesn't seem so outrageous to me. Remember that JFFS2 is 
a log-structured file system so each write appends another node to the 
log.  Old nodes aren't recovered until garbage collection is done. Er. I 
think.

Also, in a previous message you mentioned setting the number of required 
free blocks to zero.  Was this done in this test?  If so then (as I 
understand it) JFFS2 will not work as there are no free blocks for GCing 
so old nodes cannot be deleted thus you have no free flash left.

David Vrabel
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David Vrabel, Design Engineer

Arcom                         Tel: +44 (0)1223 411200 ext. 3233
Clifton Road                  Fax: +44 (0)1223 403400
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