Ulrich Windl wrote:
>>> Howard Chu <hyc(a)symas.com> schrieb am 25.01.2014 um
19:07 in Nachricht
<52E3FD6E.9070906(a)symas.com>:
> Markus Doppelbauer wrote:
>> Hello,
>> We are using BerkeleyDB since a decade - but we are searching for something
>> more lightweight. LMDB is what we are looking for ... ^^
>> The small code and the benchmark-results are very impressive!
>> A question: We have a server with 4 GB RAM. One of the BerkeleyDB-files has
>> about 20 GB.This particular database is a kind of archive - hardly read and
> hardly
>> written (maybe once per minute).
>> Is it possible to "mmap()" a 20 GB database into the RAM?
>
> Yes.
>
>> If yes, will the server
>> start "swapping"?
>
> No.
This is only true (AFAIK)
You've already demonstrated multiple times that "as far as you know" is not
far at all.
if the applications uses huge pages or memory
locking. In other
cases it depends on the OS and the other applications.
In general mmap files "swap" onto themselves, and you would
not call it
"swapping" in the usual sense...
Thus, the answer is "No", as I already said, and you have added no value to
the discussion.
Ulrich
--
-- Howard Chu
CTO, Symas Corp.
http://www.symas.com
Director, Highland Sun
http://highlandsun.com/hyc/
Chief Architect, OpenLDAP
http://www.openldap.org/project/