directory-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Emmanuel Lecharny" <>
Subject Re: Usage of JDBM : Experience feedbacks
Date Wed, 22 Oct 2008 10:59:43 GMT
On Wed, Oct 22, 2008 at 11:20 AM, Florent Gratta
<> wrote:
> Hi All,
> I am currently Project Lead at Sicap, a Swiss company which designs
> softwares for mobile operators and the mobile network world in general.
> We are going to use a BTree library to index entries of csv files. We have
> identified JDBM library ( and we have seen that
> you are currently using it in Apache Directory.
> As there is no more tracker activity on this project and it seems that it is
> the same thing for support, we would like to know if JDBM is stable:

There is no activity, mainly because it's damn stable ! It's now 6
years we are using it, and we haven't found a bug... We just have
asked for a couple of modification, just fonctional additions.
> è       Have you encountered problems when you use this library in
> multithreaded mode: Several concurrent inserts at a time?

So far, nope.

> è       What is the behaviour of the library when we shut down with
> emergency? Is it robust? By this way, does BTree file could be corrupted?

Good question. I guess they could, but nothing a backup can't restore ...

> è       Do you encountered performance lack in some cases?

Some very preliminary tests we have done against a major and well none
OSS BTree shows that it's 20 time faster. Now, it's all about how much
memory you have.

> è       Is there some limitations or lacks: Size of the index chain, cache
> size etc ...

None that we can know about. We have injected more than 5 millions 1k
elements into it with something like 5 index, no problem.

> è       Etc ...
> We are very interested on your feedbacks and experiences on JDBM library
> usage ?

So far, just a perfect piece of software.

FYI, there is still some activity around JDBM, but it's slow.

Hope it helps.

Emmanuel Lécharny

View raw message