Disk Based Queuing 5.2 – set by default??

[Jim Kosloskey]

Anyone know if Disk Based Queing is effective automatically in 5.2 or is still dormant until configured in the NetConfig?

I thought somewhere I heard Disk Based Queuing would be turned on automatically beginning with some release and 5.2 might be included.

Any enlightenment??

Thanks,

Jim Kosloskey

email: jim.kosloskey@jim-kosloskey.com 30+ years Cloverleaf, 60 years IT – old fart.

Topic

[James Cobane]

Jim,

I believe disk-based queueing is turned on by the engine automatically in 5.2 and above after 50 messages are queued.  There is a parameter to force it to remain off until a higher value is reached:

DISKQ_MINMSGS (default is 50), in the “hci” users environment.

Recommended setting would be DISKQ_MINMSGS=5000 and place it in the file “/home/hci/.profile” .  After making this envirnoment variable change, all hci user engines and the hcihostserver process will have to be restarted so that the new setting well be used.

[Rob Abbott]

I had development explain this to me a while ago, here is the text:

Quote:

There are several factors in determining disk-based queuing:

1) The queue size: If the queue depth is less than a certain number, the disk queue is not engaged. The number is set by the environment variable DISKQ_MINMSGS (default 50)

Two and Three only apply if the queue depth is larger than the minimum.

2) Virtual memory percent used: If more than 75% of virtual memory is used then the message is stored to disk.

Three only applies if virtual memory utilization <= 75% 3) If the process threshold is set and the total size of all messages in memory is greater than the threshold then the message is stored to disk. Default is never to store on disk. Conclusions: The best way to be sure that nothing goes to disk is to set DISKQ_MINMSGS very high. Then nothing else matters. If the customer

Rob Abbott
Cloverleaf Emeritus

[Jim Kosloskey]

Thanks Jim and Rob.

We noticed some increased Disk I/O during peak period.

Your responses will make it possible for us to properly analyze the situation.

Jim Kosloskey

email: jim.kosloskey@jim-kosloskey.com 30+ years Cloverleaf, 60 years IT – old fart.

[Kevin Scantlan]

If I make a change in the DISKQ_MINMSGS variable in the .profile for hci, when will it become effective.  Will we have to drop the whole engine, or it on a process by process basis?

[Rob Abbott]

It’s an environment variable — all environment settings for the current shell are passed to a process when it starts.

So you can set it from the command line and start the engine with hcienginerun if you like.

If you use the GUI, you will need to modify the environment variable and bounce the hostserver for it to pick up any environment changes.  You will then need to restart your engine(s) through the GUI for changes to take effect.

Note that if you make the change in .profile you will need to log out and log back in for the new environment setting to be picked up by your shell.

Rob Abbott
Cloverleaf Emeritus

[Author]

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