Re: [RFC PATCH v2 1/3] Btrfs: add the Probabilistic Skiplist

On Wed, Jan 11, 2012 at 10:06:47AM +0800, Liu Bo wrote:

quoted

or you can set the maxlevel during skiplist creation, or predefine a
"small" skiplist with compile-time-set level to whatever < 16.

this can be tuned later of course.

Yes, I do set the maxlevel to 16 at the creation of a skiplist.

Here 4^(16 - 1) is 2^30, I don't think this is enough for some severe workloads which build large
amount of fragments.

2^30 is ~one bilion, still a lot :) but I understand your concerns.

Maybe we should make the maxlevel self-update.

yeah, but this is IMO not necessary for the first version.

quoted

I suggest to pick the full prefix "skiplist_" instead of just "sl_",
it'll be IMHO more readable and googlable. (Out of curiosity I grepped
for the sl_ prefix and it's used by drivers/net/slip/slip.c).

I did hesitate for a while between "skiplist_" and "sl_"...
and I just wanna make it be similar to "rb_".

Anyway, I'm ok with "skiplist_".

thanks.


david