On 8/18/05, Eric Dumazet [off-list ref] wrote:

Andi Kleen a écrit :

quoted

quoted

(because of the insane struct file_ra_state f_ra. I wish this structure
were dynamically allocated only for files that really use it)

How about you submit a patch for that instead?

-Andi

OK, could you please comment this patch ?

The problem of dynamically allocating the readahead state data is that the allocation can fail and should not be fatal.
I made some choices that might be not good.

I also chose not to align "file_ra" slab on SLAB_HWCACHE_ALIGN because the object size is 10*sizeof(long), so alignment would loose
6*sizeof(long) bytes for each object.


[PATCH]

* struct file cleanup : the very large file_ra_state is now allocated only on demand, using a dedicated "file_ra" slab.
        64bits machines handling lot of sockets can save about 72 bytes per file.
* private_data : The field is moved close to f_count and f_op fields to speedup sockfd_lookups

Why not keep the comment or fix it?

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