What is the impact of increasing CommandBufferSize (_PACKET_SIZE)?

[Vitaliy-R]

Hi,

By default CommandBufferSize for BW is set to 128kB. Have anyone tried to play with bigger settings (let's say 0.5 or even 1MB)? What are the impacts of increased buffer size on the performance, memory consumption etc?

Thank you,

-Vitaliy

[Former Member]

Hi,

never ever think of changing these constraints. Noone will support if you will have trouble out of this!

Changing this parameter in its allowed range will allow shorter/longer commands (but you do not want to send commands of that size, do you?) and will allow the kernel to return more/less result-records at once to the client-tools.

If commands are really long it may happen that internal structures are not able to handle the internal representation of the command and the command will return an error out of this.

When returning many resultrows at once, we cannot assure that client-tools and internal structures of kernel and client tools will be able to allow more than is specified by this parameter.

Elke

[Former Member]

Hi,

noone has the ability to play around with bigger settings as bigger settings are not supported and trying to set this parameter to a bigger value will fail.

Elke

[Vitaliy-R]

Hi Elke. Thank you for your reply. But I am still trying to understand the implications, let's say why it is not supported. I am working on some technical project where I need to understand implications of CommandBufferSize manipulations.

Because technically it is possible to change the restriction by modifying constraint definition in environment settings file.

I am new to MaxDB, so might make some wrong statements and then please correct me.

Thank you,

-Vitaliy