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Hi All,<br>
<br>
Recently, I had a problem. A database query in C blocked <br>
the entire mzscheme environment. I solved this by using<br>
scheme_block_until, and executing the database query in<br>
an operating system thread. <br>
<br>
Results of this were very satisfying and can be found here:<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.elemental-programming.org/epwiki/scheme%20oodb-perftests.html">http://www.elemental-programming.org/epwiki/scheme%20oodb-perftests.html</a><br>
<br>
Now, the queries in these performance tests were executed<br>
directly from scheme, using a function call to call the functions in<br>
the client-handler, see the picture in:<br>
<br>
<a class="moz-txt-link-freetext" href="http://www.elemental-programming.org/epwiki/scheme%20oodb.html">http://www.elemental-programming.org/epwiki/scheme%20oodb.html</a><br>
<br>
Now, I've added the <i>client-connection-handler</i>, which handles the<br>
TCP/IP protocol, i.e., the OODB has been given a TCP/IP interface.<br>
<br>
Clients can call RPC, via the client-connection-handler, functions<br>
in the <i>client-handler</i>. client-connection-handlers are started
as a<br>
mzscheme thread from a client acceptor (not in the picture), which<br>
handles TCP accepts.<br>
<br>
Suddenly, I'm having the same behaviour as before again. The<br>
database queries seem to be executed synchronously.<br>
<br>
What can be the cause of this? Is it multiple scheme_block_until()<br>
calls? (because maybe scheme_block_until() is also used with the<br>
TCP/IP mechanisms in mzscheme)?<br>
<br>
Thanks in advance for any answers, I'm really lost here!<br>
<br>
Hans Oesterholt.<br>
<br>
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