[Sequoiadb-discuss] Sequoia gets stuck (probably) because of SELECT...FOR UPDATE

[rohit d. <roh...@gm...>]

Hi,

I have been facing some problem with sequoia. I am trying to run
BenchmarkSql-2.3 (http://sourceforge.net/projects/benchmarksql/) with
sequoia over two postgresql-7.3 servers but it seems to get stuck
indefinitely at the same point. I think it's happening because of the
SELECT...FOR UPDATE but not really sure how :( It seems that the
transactions are getting into a deadlock. Here's the out put when I turned
on the debug mode.

02:56:49,388 DEBUG controller.core.PingResponder Received ping data from /
127.0.0.1
02:56:49,388 DEBUG controller.core.PingResponder Response to ping sent to /
127.0.0.1
02:56:49,775 DEBUG sequoia.controller.loadbalancer Building wait-for
graph...
02:56:49,776 DEBUG sequoia.controller.loadbalancer new_order locked by 64
02:56:49,777 DEBUG sequoia.controller.loadbalancer district locked by 65
02:56:49,777 DEBUG sequoia.controller.loadbalancer warehouse locked by 65
02:56:49,777 DEBUG sequoia.controller.loadbalancer Walking wait-for graph...
02:56:49,778 DEBUG sequoia.controller.loadbalancer 64 waits for district
locked by 65
02:56:49,779 DEBUG sequoia.controller.loadbalancer 68 waits for new_order
locked by 64
02:56:49,779 DEBUG sequoia.controller.loadbalancer     64 waits for
district locked by 65
02:56:49,779 DEBUG sequoia.controller.loadbalancer 67 waits for warehouse
locked by 65
02:56:49,779 DEBUG sequoia.controller.loadbalancer 66 waits for new_order
locked by 64
02:56:49,779 DEBUG sequoia.controller.loadbalancer     64 waits for
district locked by 65
02:56:49,779 DEBUG sequoia.controller.loadbalancer Choosing victim node...
02:56:49,779 DEBUG sequoia.controller.loadbalancer 0 cycles detected
02:56:49,779 DEBUG sequoia.controller.loadbalancer No victim
02:56:50,389 DEBUG controller.core.PingResponder Received ping data from /
127.0.0.1
02:56:50,389 DEBUG controller.core.PingResponder Response to ping sent to /
127.0.0.1



Here's my configuration file..

<?xml version="1.0" encoding="UTF-8"?>^M
<!DOCTYPE SEQUOIA PUBLIC "-//Continuent//DTD SEQUOIA @VERSION@//EN" "
http://sequoia.continuent.org/dtds/sequoia-@VERSION@.dtd">^M
^M
<SEQUOIA>^M
^M
  <VirtualDatabase name="tpcw">^M
^M
    <AuthenticationManager>^M
      <Admin>^M
        <User username="postgres" password=""/>^M
      </Admin> ^M
      <VirtualUsers>^M
        <VirtualLogin vLogin="postgres" vPassword=""/>^M
      </VirtualUsers>^M
    </AuthenticationManager>^M
^M
    <DatabaseBackend name="localhost" driver="org.postgresql.Driver"
driverPath="/home/rohit/Software/CJDBC/sequoia-2.10.10-bin/drivers/postgresql7.3.jar"
url="jdbc:postgresql://localhost:6551/tpcw" connectionTestStatement="select
now()">^M

      <ConnectionManager vLogin="postgres" rLogin="postgres" rPassword="">^M
        <VariablePoolConnectionManager initPoolSize="20" minPoolSize="5"
maxPoolSize="0" idleTimeout="180" waitTimeout="0"/>^M
      </ConnectionManager>^M
    </DatabaseBackend>^M
^M
    <DatabaseBackend name="Remote" driver="org.postgresql.Driver"
driverPath="/home/rohit/Software/CJDBC/sequoia-2.10.10-bin/drivers/postgresql7.3.jar"
url="jdbc:postgresql://192.168.164.136:6552/tpcw"
connectionTestStatement="select now()">^M
      <ConnectionManager vLogin="postgres" rLogin="postgres" rPassword="">^M
        <VariablePoolConnectionManager initPoolSize="20" minPoolSize="5"
maxPoolSize="0" idleTimeout="180" waitTimeout="0"/>^M
      </ConnectionManager>^M
    </DatabaseBackend>^M
    <RequestManager>^M
      <RequestScheduler>^M
         <RAIDb-1Scheduler level="passThrough"/>^M
      </RequestScheduler>^M
^M
      <RequestCache>^M
         <MetadataCache/>^M
         <ParsingCache/>                 ^M
         <ResultCache granularity="table" />^M
      </RequestCache>^M
^M
      <LoadBalancer transactionIsolation="serializable">^M
         <RAIDb-1>^M
            <WaitForCompletion policy="all"
            deadlockTimeoutInMs="30000"/>^M
            <RAIDb-1-RoundRobin/>^M
         </RAIDb-1>^M
      </LoadBalancer>^M
    </RequestManager>^M
^M
  </VirtualDatabase>^M
^M
</SEQUOIA>^M

If anybody has anu idea why this happens please let me know. I would
appreciate it a lot. Thanks in advance.

Regards,
Rohit