threads/85112: Resource temporarily unavailable reading from sockets with Java/libpthread/jdbc

[Nick Johnson]

>Number:         85112
>Category:       threads
>Synopsis:       Resource temporarily unavailable reading from sockets with Java/libpthread/jdbc
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    freebsd-threads
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Aug 19 05:10:08 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Nick Johnson
>Release:        FreeBSD 5.4-STABLE i386
>Organization:
morons.org 
>Environment:
System: FreeBSD turing.morons.org 5.4-STABLE FreeBSD 5.4-STABLE #4: Mon Aug 15 21:22:19 PDT 2005 root at turing.morons.org:/usr/src/sys/i386/compile/TURING i386

Java 1.4.2-p7 built from ports
Postgresql 8.0.3 built from ports; however still using the Postgresql 7.4 JDBC driver

	
>Description:
When attempting to get a database connection with Java linked to libpthread, a socket exception is thrown:

java.net.SocketException: Resource temporarily unavailable
        at java.net.SocketInputStream.socketRead0(Native Method)
        at java.net.SocketInputStream.read(SocketInputStream.java:129)
        at java.io.BufferedInputStream.fill(BufferedInputStream.java:183)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:201)
        at org.postgresql.PG_Stream.ReceiveChar(PG_Stream.java:139)
        at org.postgresql.jdbc1.AbstractJdbc1Connection.openConnection(AbstractJdbc1Connection.java:190)
        at org.postgresql.Driver.connect(Driver.java:122)
        at java.sql.DriverManager.getConnection(DriverManager.java:512)
        at java.sql.DriverManager.getConnection(DriverManager.java:193)
        at net.spatula.news.Utils.getJDBCconnection(Utils.java:816)

Here is the code from getJDBCconnection, verbatim, including ugliness just for fun...

    public static synchronized Connection getJDBCconnection() {
        try {
            Class.forName("org.postgresql.Driver");
        } catch (Exception e) {
            e.printStackTrace();
        }
        int retryCount = 5;
        while (retryCount >0) {
            try {
                //XXX database name and username should be properties
                String dbURL = "jdbc:postgresql://"+ getProperty("spatula.dbhost")+":"+
                    getProperty("spatula.dbport")+"/morons.org?user=www&password="+
                    getProperty("spatula.dbpass");
                Connection c = DriverManager.getConnection(dbURL);  // <--- this is line 816
                return c;
            } catch (Exception e) {
                e.printStackTrace();
            }
            retryCount--;
            try {
                Thread.sleep(200 + (int)(Math.random()*50.0));
            } catch (Exception e) {}
        }
        return null;
    }

This fails every time when java links against libpthread and works every time when it is linked against libc_r.

I'm not entirely sure, but this may have started showing itself after I added this to /etc/make.conf:

	CPUTYPE?=i686
	CFLAGS=-O2 -pipe

or it may be totally unrelated.  See also threads/84778 (http://www.freebsd.org/cgi/query-pr.cgi?pr=84778) which was previously
preventing me from getting far enough to make a database connection.  (Once the class files were compiled with a process
linked against libc_r, they were in place for a process linked against libpthread to use.)

	
>How-To-Repeat:

Try to get a database connection.
	
>Fix:

Workaround is to configure the linker to use libc_r for all Java processes
in /etc/libmap.conf:

[/usr/local/jdk1.4.2/] 
libpthread.so.1         libc_r.so.5
libpthread.so           libc_r.so

	


>Release-Note:
>Audit-Trail:
>Unformatted: