<docbook><section><title>VirtTipsAndTricksGuideNotRespondingHTTP</title><title>What should I do if the Virtuoso Server is not responding to HTTP requests?</title>What should I do if the Virtuoso Server is not responding to HTTP requests?
<para> </para>
<bridgehead class="http://www.w3.org/1999/xhtml:h2">What?</bridgehead>
 Manage Virtuoso Server when it is not responding to HTTP requests.<bridgehead class="http://www.w3.org/1999/xhtml:h2">Why?</bridgehead>
 Observe what activity might be the cause and to remove pending transactions which then will result in enabling the server to start responding to HTTP requests again.<bridgehead class="http://www.w3.org/1999/xhtml:h2">How?</bridgehead>
<para>Assume the Virtuoso server  is not responding to HTTP requests although SQL connection is working.
 In order to determine what activity is being performed that might account for this:</para>
<orderedlist spacing="compact"><listitem>Check the status: <programlisting>SQL&gt; status(&#39;&#39;);
REPORT
VARCHAR
_______________________________________________________________________________


OpenLink Virtuoso VDB Server
Version 06.02.3129-pthreads for Linux as of Mar 16 2011 
Registered to Uriburner (Personal Edition, unlimited connections)
Started on: 2011/03/17 10:49 GMT+60
 
Database Status:
  File size 0, 37598208 pages, 7313125 free.
  1000000 buffers, 993399 used, 76771 dirty 0 wired down, repl age 25548714 0 w. io 0 w/crsr.
  Disk Usage: 2642884 reads avg 4 msec, 30% r 0% w last  1389 s, 1557572 writes,
    15331 read ahead, batch = 79.  Autocompact 308508 in 219226 out, 28% saved.
Gate:  71130 2nd in reads, 0 gate write waits, 0 in while read 0 busy scrap. 
Log = virtuoso.trx, 14922248 bytes
VDB: 0 exec 0 fetch 0 transact 0 error
1757362 pages have been changed since last backup (in checkpoint state)
Current backup timestamp: 0x0000-0x00-0x00
Last backup date: unknown
Clients: 5 connects, max 2 concurrent
RPC: 116 calls, -1 pending, 1 max until now, 0 queued, 2 burst reads (1%), 0 second brk=9521074176
Checkpoint Remap 331113 pages, 0 mapped back. 1180 s atomic time.
    DB master 37598208 total 7313125 free 331113 remap 40593 mapped back
   temp  569856 total 569851 free
 
Lock Status: 52 deadlocks of which 0 2r1w, 86078 waits,
   Currently 1 threads running 0 threads waiting 0 threads in vdb.
Pending:


25 Rows. -- 1274 msec.
SQL&gt; 
</programlisting></listitem>
<listitem>Connect with the PL debugger and see what is running currently using the  info threads call: <programlisting>$ isql 1111 dba &lt;password&gt; -D
DEBUG&gt; info threads
</programlisting></listitem>
<listitem>This should return the current code being executed by the Sever.
</listitem>
<listitem>Run <ulink url="http://docs.openlinksw.com/virtuoso/fn_txn_killall.html">txn_killall()</ulink> to kill any pending transactions which may enable the server to start responding to HTTP requests again: <programlisting>SQL&gt; txn_killall();

Done. -- 866 msec.
</programlisting></listitem>
</orderedlist><bridgehead class="http://www.w3.org/1999/xhtml:h2">Related</bridgehead>
<itemizedlist mark="bullet" spacing="compact"><listitem><ulink url="VirtTipsAndTricksGuide">Virtuoso Tips and Tricks Collection</ulink> </listitem>
</itemizedlist></section></docbook>