CSS 11500 - calculation of "load"

[sthon-dbsys]

Hi together,

can everone explain me, how the "load calculation" works in balance aca.

1. is the load calculated from the keepalives or from

every tcp flow to the service ?

2. which parameter are used to calculate the flow (e.g. answer time)

3. I am wondering about the following.

if I have onyl a few sessions to one service the load is very high (up to 200) over hours, if I have up to 100 sessions per service the load is around 50)

high load:

Name: Hits: Wgt: State: Ld: KAlive: Conn: DNS:

----- ----- ----- ------ --- ------- ----- ----

fred 586,260 S-1 Alive 128 HTTP:GET 2 0

frodo 786,690 S-1 Alive 196 HTTP:GET 1 0

low load:

Name: Hits: Wgt: State: Ld: KAlive: Conn: DNS:

----- ----- ----- ------ --- ------- ----- ----

fred 629,025 S-1 Alive 46 HTTP:GET 94 0

frodo 837,645 S-1 Alive 27 HTTP:GET 134 0

thanks in advance

[Gilles Dufour]

Here is an answer.

Not too much detail but I would be too long with the details.

The CSS11000 uses the normalized average response times from start (SYN) to

finish (FIN) of the TCP connections between clients and servers to determine

a load value for each server. The server with the lowest average response

time is given a load value of 2. The load ranges are from 2 to 255, and they

are calculated separately for long and short (<15K) files and then averaged

together. The load calculation is done against flow teardown reports. These

reports show SYN to FIN time (ticks) and the number of bytes. (NOTE:

Persistent connections with a total of >15k will be classified as long

flows.)

(NOTE: Keepalives are not included in the load calculation. However, the

impact of these keepalives on the server would be reflected in the response

times of the other flows going to the service if they presumably affected

the load on the server.)

Gilles.

[sthon-dbsys]

thansk for the clear answer.

One last question:

in which timesteps the load is calculated ?

It is time based or connection based ?

[Gilles Dufour]

you can do a 'show load' to see the timer.

Gilles.

[sthon-dbsys]

thanks for the info.

Found the docu in Rel 7.4

thanks