Kevin, The whole method of figuring out if the DB is being used by another HSQLDB process needs a revamp in the very new future.
But in the meantime, re. connection pool with 20 connections? If these connections are to an HSQLDB server, they wouldn't be a problem, but if they are standalone database connections, they definitely are THE problem. Your original message had: at org.hsqldb.jdbcConnection.openStandalone(jdbcConnection.java:926) I suspect the connection pool is trying to open the same database 20 times. What is the connection URL? Fred Toussi ----- Original Message ----- From: "Kevin A. Burton" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, March 07, 2002 9:35 PM Subject: [Hsqldb-developers] MORE The database is already in use by another process > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > > OK... > > I spent some type patching isAlreadyOpen and distributing updates .jar files to > my users. > > Here is what I learned. > > - - it isn't a synchronization issue in isAlreadyOpen. I created a synchronized > block around Log.class and it still fails. > > - - the file DOES exist. > > - - the delete() == false call is what is causing this. > > - - canRead and canWrite both return true :( > > I think the problem is the way that the file is opened. Java states that on > some systems an open file is exclusive. > > I think the problem is that on Windows, file operations in Java under Windows > are exclusive. > > Maybe we should rewrite (make sense) Log.java to make sure that we don't try to > load the properties file while we are trying to save it. Looking at the current > code, it appears that someone could call open in one thread (DBConnection) while > isAlreadyOpen is trying to be called in another thread. > > Under UNIX/Linux... these are not exclusive and at least from Java, there is no > way to make them operate so. > > So... my thinking (no suggestion yet) is that we just use a static synchronizer > so that the properties file is not written to during another write/read > operation. > > Does that make sense? It looks like we only have to modify isAlreadyOpen, > loadProperties and saveProperties... > > As an aside. Could a DB connection pool raise this issue? It seems that it > might. I am using Turbine's DB connection pool with 20 connections. This > seems to work fine under Linux... obviously not find under Windows :) > > Kevin > > - -- > Kevin A. Burton ( [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED] ) > Location - San Francisco, CA, Cell - 415.595.9965 > Jabber - [EMAIL PROTECTED], Web - http://relativity.yi.org/ > > Without enlightenment, there is only ignorance. > -- famous Zen Koan > > > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.0.6 (GNU/Linux) > Comment: Get my public key at: http://relativity.yi.org/pgpkey.txt > > iD8DBQE8h904AwM6xb2dfE0RAnKhAJ9Ax19sY6WNvumO9ct1iW/hGBb/sACaA/BF > kUio7UiJm1BHcXvaYOW33Y0= > =NzDY > -----END PGP SIGNATURE----- > > _______________________________________________ > hsqldb-developers mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/hsqldb-developers _______________________________________________ hsqldb-developers mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/hsqldb-developers
