Comments on: Multiple threads opening the same Berkeley DB in Tcl http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/ Everything that comes out of Dossy, from the strange to the banal. Sat, 13 Mar 2010 03:30:11 +0000 http://wordpress.org/?v=2.9.1 hourly 1 By: tedka http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-70698 tedka Thu, 12 Mar 2009 00:30:27 +0000 http://dossy.org/archives/000307.html#comment-70698 I have tried Berkeley DB on Windows for a week. Works well with a single thread. But when I try to use two threads reading at the same time that share a Db handle (there is no writing), I get an "Invalid argument" exception after approximately 5 seconds after I created threads. I open the Db handle with DB_THREADS in main thread, and then create two worker threads that use this handle, this does not help. I followed the documentation which says that this is enough and no locking or serializing access to Db handle are necessary (as well as using an environment). So now I have two options: 1) Use a single thread (which is actually not an option) 2) Throw Berkeley DB away. Looks like yet another raw and poorly documented and poorly supported product not better than Microsoft's. I have tried Berkeley DB on Windows for a week. Works well with a single thread. But when I try to use two threads reading at the same time that share a Db handle (there is no writing), I get an “Invalid argument” exception after approximately 5 seconds after I created threads. I open the Db handle with DB_THREADS in main thread, and then create two worker threads that use this handle, this does not help. I followed the documentation which says that this is enough and no locking or serializing access to Db handle are necessary (as well as using an environment). So now I have two options: 1) Use a single thread (which is actually not an option) 2) Throw Berkeley DB away.
Looks like yet another raw and poorly documented and poorly supported product not better than Microsoft’s.

]]> By: Dossy http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-436 Dossy Mon, 16 Jun 2008 14:39:50 +0000 http://dossy.org/archives/000307.html#comment-436 Sorry, Alexey - not yet. You may want to ask for help on the AOLserver mailing list - someone else may be able to help you in the meantime. Sorry, Alexey – not yet. You may want to ask for help on the AOLserver mailing list – someone else may be able to help you in the meantime.

]]> By: Alexey Pechnikov http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-435 Alexey Pechnikov Mon, 16 Jun 2008 11:40:57 +0000 http://dossy.org/archives/000307.html#comment-435 Are you wrote a HOWTO on how to set up and use nsproxy? I want to try nsproxy in aolserver 4.5 on debian lenny (testing) but have no good examples. Are you wrote a HOWTO on how to set up and use nsproxy? I want to try nsproxy in aolserver 4.5 on debian lenny (testing) but have no good examples.

]]> By: Alexey Pechnikov http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-434 Alexey Pechnikov Thu, 07 Feb 2008 07:08:03 +0000 http://dossy.org/archives/000307.html#comment-434 This HOWTO will be very usefull. This HOWTO will be very usefull.

]]> By: Dossy http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-433 Dossy Thu, 07 Feb 2008 02:24:52 +0000 http://dossy.org/archives/000307.html#comment-433 Unfortunately, there's no good example code. I would start with AOLserver 4.5 and nsproxy, and load the BDB Db_tcl module in the proxy and access it there--as proxies are single-threaded tclsh processes. When I get a chance, I'll try to write-up a HOWTO on how to set up and use nsproxy. Unfortunately, there’s no good example code. I would start with AOLserver 4.5 and nsproxy, and load the BDB Db_tcl module in the proxy and access it there–as proxies are single-threaded tclsh processes.

When I get a chance, I’ll try to write-up a HOWTO on how to set up and use nsproxy.

]]> By: Alexey Pechnikov http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-432 Alexey Pechnikov Wed, 06 Feb 2008 23:50:33 +0000 http://dossy.org/archives/000307.html#comment-432 Do exists the correct solution for use BDB in a single-threaded environment of AOL Server? I try any ideas but it's bad work. Do you use BDB with AOL? Do exists the correct solution for use BDB in a single-threaded environment of AOL Server? I try any ideas but it’s bad work. Do you use BDB with AOL?

]]> By: Dossy http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-431 Dossy Wed, 06 Feb 2008 22:44:03 +0000 http://dossy.org/archives/000307.html#comment-431 Alexey: The only solution that will be correct is to use Berkeley DB's Tcl API in a single-threaded environment, at least until the day when they rework their implementation to be properly thread-safe. Alexey: The only solution that will be correct is to use Berkeley DB’s Tcl API in a single-threaded environment, at least until the day when they rework their implementation to be properly thread-safe.

]]> By: Alexey Pechnikov http://dossy.org/2006/07/multiple-threads-opening-the-same-berkeley-db-in-tcl/comment-page-1/#comment-430 Alexey Pechnikov Wed, 06 Feb 2008 22:07:31 +0000 http://dossy.org/archives/000307.html#comment-430 It's work from tcl library, but don't work from adp pages (or we must create threads for each adp page). Do you know a better method? It’s work from tcl library, but don’t work from adp pages (or we must create threads for each adp page). Do you know a better method?

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