[Fwd: Re: Caching of reads]

[Alex J Lennon]

> There should be more debug info than that from JFFS2, shouldn't there?

That's what I get with verbosity = 1 
I've attached another partial log generated with verbosity = 3

> Are you sure that's right? Those sizes look suspicious. But it definitely

Absolutely not - but it is what the kernel is logging.

> looks like some of those nodes are being read repeatedly - I 
> don't know why
> they're being dropped from the page cache. What kernel, precisely?

kernel.org 2.4.14, patched with the Linus VM fix
(http://www.uwsg.indiana.edu/hypermail/linux/kernel/0111.0/1084.html)

.config attached also

> Please could you turn that off?

Given the option it would be :(

Any thoughts on where we should be looking ?

Best,

-Alex

> -----Original Message-----
> From: linux-mtd-admin at lists.infradead.org
> [mailto:linux-mtd-admin at lists.infradead.org]On Behalf Of David Woodhouse
> Sent: Friday, November 16, 2001 4:05 PM
> To: Alex J Lennon
> Cc: Ian Campbell; Linux MTD Mailing List
> Subject: Re: [Fwd: Re: Caching of reads] 
> 
> 
> 
> 
> > An strace seems to show it's related to the fork(), shortly 
> after the fork()
> 
> There should be more debug info than that from JFFS2, shouldn't there?
> 
> > <7>Node read from 00d9d8f4: node_crc f3b6e771, calculated CRC 
> f3b6e771. dsize 7, csize 7, offset 0, buf c3be1ea0
> > <7>Node read from 00cec5c0: node_crc b16a4fa6, calculated CRC 
> b16a4fa6. dsize b, csize b, offset 0, buf c3beec60
> > <7>Node read from 00c55d1c: node_crc 544bdb58, calculated CRC 
> 544bdb58. dsize d, csize d, offset 0, buf c3be1ea0
> > <7>Node read from 00d9d8f4: node_crc f3b6e771, calculated CRC 
> f3b6e771. dsize 7, csize 7, offset 0, buf c3be1ea0
> > <7>Node read from 00d9d8f4: node_crc f3b6e771, calculated CRC 
> f3b6e771. dsize 7, csize 7, offset 0, buf c3be1ea0
> > <7>Node read from 00cec5c0: node_crc b16a4fa6, calculated CRC 
> b16a4fa6. dsize b, csize b, offset 0, buf c3beec60
> > <7>Node read from 00c55d1c: node_crc 544bdb58, calculated CRC 
> 544bdb58. dsize d, csize d, offset 0, buf c3be1ea0
> 
> Are you sure that's right? Those sizes look suspicious. But it definitely
> looks like some of those nodes are being read repeatedly - I 
> don't know why
> they're being dropped from the page cache. What kernel, precisely?
> 
> 
> > The message in this transmission is sent in confidence for the
> > attention of the addressee only and should not be disclosed to any
> > other party. Unauthorised recipients are requested to preserve this
> > confidentiality. Please advise the sender if the addressee is not
> > resident at the receiving end. 
> 
> Please could you turn that off?
> 
> --
> dwmw2
> 
> 
> 
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/
> 
> _____________________________________________________________________
> This message has been checked for all viruses by MessageLabs 
> Virus Control Centre.
> 

_____________________________________________________________________
The message in this transmission is sent in confidence for the attention of the addressee only and should not be disclosed to any other party. Unauthorised recipients are requested to preserve this confidentiality. Please advise the sender if the addressee is not resident at the receiving end.

This message has been checked for all viruses by MessageLabs Virus Control Centre. 

Company registered in England No. 1608562.
Registered Office: Unit 8, Clifton Road, Cambridge, CB1 7EA, United Kingdom, Tel: 01223 411200.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: jffs2.log
Type: application/octet-stream
Size: 17757 bytes
Desc: not available
Url : http://lists.infradead.org/pipermail/linux-mtd/attachments/20011116/a0369541/attachment.obj 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: .config
Type: application/octet-stream
Size: 17552 bytes
Desc: not available
Url : http://lists.infradead.org/pipermail/linux-mtd/attachments/20011116/a0369541/attachment-0001.obj