From: Daniel Berger <djberge@...>
Date: 2003-04-09T04:42:21+09:00
Subject: Re: Problem with timeout for DBI on Solaris

Brian Candler wrote:
> 
<snip>
> 
> For Oracle, you can try using the ruby-oci8 library from RAA which supports
> non-blocking queries (although I don't know if it supports non-blocking
> connect). It comes with its own DBD which you have to install manually into
> /usr/local/lib/ruby/site_ruby/1.6/DBD/OCI8/OCI8.rb
> 
> Then modify it as follows:
> 
> require 'dbi'
> require 'DBD/OCI8/OCI8'
> 
> module DBI
> module DBD
> module OCI8
> class Driver
>   def connect( dbname, user, auth, attr )
>     handle = ::OCI8.new(user, auth, dbname, attr['Privilege'])
>     handle.non_blocking = true if attr['NonBlocking']    #<<<< add this line
>     return Database.new(handle, attr)
>   rescue OCIError => err
>     raise DBI::DatabaseError.new(err.message, err.code)
>   end
> end
> end
> end
> end
<snip>

I installed the oci8 package and made the changes you suggested, but no
luck.
In fact, it appears to hang in the ::OCI.new call.  A simple "puts"
statement
after that call shows me that it is never invoked on my system.

Stepping through the debugger, I can see that it's hanging on the
do_ocicall()
method in the oci8.rb file.  It steps in the first time, yields back
out, tries
to step back in, and that's where it hangs.

snippet of debugger session:

/usr/local/lib/ruby/site_ruby/1.6/dbi/dbi.rb:550:    db =
@handle.connect(db_args, user, auth, new_params)
(rdb:1) s
/usr/local/lib/ruby/site_ruby/1.6/DBD/OCI8/OCI8.rb:25:    handle =
::OCI8.new(user, auth, dbname, attr['Privilege'])
(rdb:1) s
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:64:    if @@env.nil?
(rdb:1) n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:65:      if
OCIEnv.respond_to?("create")
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:66:   @@env = OCIEnv.create()
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:73:    case privilege
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:74:    when nil
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:75:      privilege =
OCI_DEFAULT
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:84:    @svc =
@@env.alloc(OCISvcCtx)
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:85:    @srv =
@@env.alloc(OCIServer)
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:86:    @auth =
@@env.alloc(OCISession)
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:87:    @ctx = [0, Mutex.new,
nil]
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:89:   
@auth.attrSet(OCI_ATTR_USERNAME, uid)
(rdb:1) @ctx
[0, #<Mutex:0x3cdf78 @locked=false, @waiting=[]>, nil]
(rdb:1) n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:90:   
@auth.attrSet(OCI_ATTR_PASSWORD, pswd)
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:91:    do_ocicall(@ctx) {
@srv.attach(conn) }
(rdb:1) @srv
#<OCIServer:0x3ce788>
(rdb:1) s
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:40:      sleep_time = 0.01
(rdb:1) n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:41:      ctx[CTX_MUTEX].lock
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:42:      ctx[CTX_THREAD] =
Thread.current
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:58:      end
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:44:   yield
(rdb:1) 
n
/usr/local/lib/ruby/site_ruby/1.6/oci8.rb:91:    do_ocicall(@ctx) {
@srv.attach(conn) }
(rdb:1) s

That's where it hangs - trying to step into the do_ocicall() the second
time.

Any ideas?  Some sort of Mutex issue perhaps?

Regards,

Dan

-- 
a = [74, 117, 115, 116, 32, 65, 110, 111, 116, 104, 101, 114, 32, 82]
a.push(117,98, 121, 32, 72, 97, 99, 107, 101, 114)
puts a.pack("C*")