Bug 50595 - Exam mode on multiple schools leads to high load on master
Exam mode on multiple schools leads to high load on master
Status: RESOLVED WONTFIX
Product: UCS@school
Classification: Unclassified
Component: UMC - Exam mode
UCS@school 4.4
Other Linux
: P5 normal (vote)
: ---
Assigned To: UCS@school maintainers
:
Depends on:
Blocks:
  Show dependency treegraph
 
Reported: 2019-12-04 16:30 CET by Christian Völker
Modified: 2023-10-26 12:04 CEST (History)
6 users (show)

See Also:
What kind of report is it?: Bug Report
What type of bug is this?: 5: Major Usability: Impairs usability in key scenarios
Who will be affected by this bug?: 2: Will only affect a few installed domains
How will those affected feel about the bug?: 2: A Pain – users won’t like this once they notice it
User Pain: 0.114
Enterprise Customer affected?:
School Customer affected?: Yes
ISV affected?:
Waiting Support:
Flags outvoted (downgraded) after PO Review: Yes
Ticket number: 2019120221000346, 2020042221000437
Bug group (optional): UCS Performance
Max CVSS v3 score:


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Description Christian Völker univentionstaff 2019-12-04 16:30:26 CET
On centralized exams schools are starting (and finishing) their exams at the same time.

A test on a high volume ucs@school system brought a load of 16 on the master server when ONE of the schools finished exam mode (luckily it had been a test).

What will happen when three or more of these schools start (and finish!) the exam mode at the same time?

This should be taken into account when further development on exam mode is done.
Comment 1 Christina Scheinig univentionstaff 2019-12-04 17:06:16 CET
I could see on the s4connector on the master that for each exam user, the original user is modified, the exam user is deleted and because of tree schools the users are member of, 9 groups were modified for each exam user.

This looks like that:
modify user
delete user
modify group
modify group
modify group
modify group
modify group
modify group
modify group
modify group
modify group
 and now the next user:
modify user
delete user
modify group
modify group
modify group
modify group
modify group
modify group
modify group
modify group
modify group

This looks not like the most performant way.
Comment 2 Ingo Steuwer univentionstaff 2020-03-30 12:15:54 CEST
is this still an issue after the modifications done in the exam mode in the last releases?
Comment 3 Sönke Schwardt-Krummrich univentionstaff 2020-03-30 12:20:24 CEST
(In reply to Ingo Steuwer from comment #2)
> is this still an issue after the modifications done in the exam mode in the
> last releases?

Yes, this part has not been adapted yet.
Comment 4 Michel Smidt 2020-03-30 14:33:24 CEST
(In reply to Sönke Schwardt-Krummrich from comment #3)
> (In reply to Ingo Steuwer from comment #2)
> > is this still an issue after the modifications done in the exam mode in the
> > last releases?
> 
> Yes, this part has not been adapted yet.

Yes, this is true, but our analyses have shown that this symptomatology does not take as much time when using the exam mode.
Therefore, we have first made other improvements to speed up the start of the exam mode.
Comment 8 Michel Smidt 2020-06-24 15:38:24 CEST
Prioritize this issue lower because the exam mode has been optimized and accelerated elsewhere. Feel free to change if desired.
Comment 9 Jan-Luca Kiok univentionstaff 2023-10-26 12:04:24 CEST
This issue has been filed against UCS@school 4.4.

UCS@school 4.4 is out of maintenance and components may have vastly changed in later releases. Thus, this issue is now being closed.

If this issue still occurs in newer versions, please use "Clone this bug" or reopen this issue. In this case please provide detailed information on how this issue is affecting you.