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Sabarna_Deb's avatar
Sabarna_Deb
Level 3
13 years ago
Solved

Maximum data streams

I am having doubts regarding "Maximum data streams" in Admin guide. Please help me to clarify whether my understanding is right or wrong (In italic format)

 

Specifies the maximum number of jobs that are allowed at one time for each selected client. (This value applies to the number of jobs on the client,even if multistreaming is not used.) = This option is restricting each client of having maximum number of [backup+restore] jobs at a time eventhough client in each job could run user-defined number of streams for each backup.
 
To change the setting, select Maximum data streams. Then scroll to or
enter a value up to 99.
The Maximum data streams property interacts with Maximum jobs per 
client [Same like maximum data streams] and Limit jobs per policy-> [ This is restricting the policy of having maximum number of jobs. I believe normally policy is creating one parent job and maximum one or two child jobs. It may create more than two or three if we specify number of copies in policy's schedule. Is this restricting from that point of view?. Please correct me]  
as follows:
■ If the Maximumdata streams property is not set, the limit is either the
one indicated by the Maximum jobs per client property or the Limit
jobs per policy property, whichever is lower. [How both is overlapping to each other? ]
■ If the Maximum data streams property is set, NetBackup ignores the
Maximum jobs per client property. NetBackup uses either Maximum
data streams or Limit jobs per policy, whichever is lower. [How both is overlapping to each other? ]
 
Overall, "Maximum data streams and Maximum jobs per client" means restricting each client's maximum number of jobs in activity moniter and "Limit jobs per policy" means restricting maximum number of jobs in activity moniter by policy. Sorry if i am wrong. 
 
Backing Up
Backup and Recovery
Basics
NetBackup
  • Yasuhisa_Ishika's avatar
    Yasuhisa_Ishika
    13 years ago

    My previous post is a bit confuing. I'm not distinguish 'job generation' and 'job going ative'.

    Here is another example folowing your case.

    • Policy A is multiplestream enabled, and has 5 streams, 2 cilents(X, Y)
    • 'Limit jobs per policy' is set to 4 in each policy.
    • 'maximum jobs per policy' is set to 3
    • storage unit has enough free stream capacity, and there are no other jobs now.

    When backup of policy A starts, 10 jobs are generated(5 on X, and 5 on Y), and these jobs go into 'Queued' state first.
    At client side, each cients can process up to 4 jobs, but at poclicy side, up to 3 jobs can run simultaneously.So, only 3 jobs can go into 'Active' state first, and rest 7 jobs stay queued.

3 Replies

  • Yasuhisa_Ishika's avatar
    Yasuhisa_Ishika
    Level 6
    13 years ago

    'maximum jobs per client' and 'maximum data streams' restrict the number of jobs in active state simultaneously on the client. By default, 'maximum data streams' is not set, and 'maximum jobs per client' is applyed to all the clients in NetBackup domain.

    'limit jobs per client' restrict the number of jobs in active state simultaneously from policy perspective.
    For examle, policy A has two client - X and Y, 'limit jobs per policy' for policy A is 3, and 'maximub jobs per client' is 2. When pocliy A is started, 4 jobs are generated, and 3 of 4 jobs become active(2 on X plus 1 on Y, or 1 on X  and 2 on Y).

  • Sabarna_Deb's avatar
    Sabarna_Deb
    Level 3
    13 years ago

    Ok. If  'limit jobs per policy' is less than  'maximub jobs per client' then that policy won't be able to run more than three jobs.  And If  'limit jobs per policy' (value 4) is greater than  'maximum jobs per client' (value 3) then each client won't be included in three different policy's active jobs....Will that policy generate more than four jobs? .....

  • Yasuhisa_Ishika's avatar
    Yasuhisa_Ishika
    Level 6
    13 years ago

    My previous post is a bit confuing. I'm not distinguish 'job generation' and 'job going ative'.

    Here is another example folowing your case.

    • Policy A is multiplestream enabled, and has 5 streams, 2 cilents(X, Y)
    • 'Limit jobs per policy' is set to 4 in each policy.
    • 'maximum jobs per policy' is set to 3
    • storage unit has enough free stream capacity, and there are no other jobs now.

    When backup of policy A starts, 10 jobs are generated(5 on X, and 5 on Y), and these jobs go into 'Queued' state first.
    At client side, each cients can process up to 4 jobs, but at poclicy side, up to 3 jobs can run simultaneously.So, only 3 jobs can go into 'Active' state first, and rest 7 jobs stay queued.