Hello everyone here!
I have a question bother me for a long time. please help me!
The question is :
I create a db env and a db.then i access the db with
muti-thread.likeut、get、del the data in db .It work well if the
application close normally.And after the application crash.It will lose
some data when restart the application.I think it is acceptable to me.
becase berkeley db data in buffer.After the application crash, the data
in buffer no flush to the backing db file.But badly,Some time after
application crash.the database corrupt and i can't use it again after
the application restart.My question is:What make the database corrupt
after the application crash?(I think may be berkeley db do some think
make it corrupt.but i don't sure)How can fix it?(I don't want the
application can't restart after the user kill it)

can some one help me?I post this for a long time.

Berkeley DB maintains state in memory for performance reasons, and to
maintain consistency between multiple threads. So when the process is
killed, the data on disk is not complete (it is missing that data in
memory).

To recover after a crash, you need to write a transactional
application. See this section of the documentation for more
information:

http://www.sleepycat.com/docs/ref/transapp/intro.html

Regards,
Michael.

Michael Cahill wrote:
Because the performance, I can't use a transactional protect in my
application! On the top I mean the data missing in memory is accepted
by me.But some time it can't use the db file again(lose all data in the
file i write before).How can guarantee the db file not corrupt and i
can't access the data i write before?

What are your performance requirements? There are many ways to
configure Berkeley DB for high performance transactions.

The only ways to ensure that files on disk are consistent when your
application starts are:

* use transactions and recovery; or
* shut down cleanly (that is, close all databases and the environment
before processes exit).

Regards,
Michael.

Michael Cahill wrote:
Thanks Michael!
My performance requirements is :insert or update or del 3000 items in
db.What i can do ?

demon... (AT) 163 (DOT) com wrote:

I means insert or update or del 3000 items per second