Connection priority [CORE728]

[firebird-automations]

Submitted by: @pcisar

Votes: 3

SFID: 807961#⁠ Submitted By: pcisar

Allow for task priority to be set by connection.

[firebird-automations]

Modified by: @pcisar

Workflow: jira \[ 10752 \] =\> Firebird \[ 15150 \]

[firebird-automations]

Commented by: PizzaProgram Ltd. (szakilaci)

The fast and easy way to implement this would be insert a Sleep() interval between rows while running a query (or update...). * it could be called during DB connection: IBDataBase1.Params.Text := 'user_name=SYSDBA'#⁠13'password=masterkey'#⁠13'lc_ctype=WIN1250'#⁠13'sleep_between_rows=10 '; //0..1000 ms

OR (and) * implement into transaction params: IBTransaction1.Params.Text := 'read_committed'#⁠13'rec_version'#⁠13'nowait'#⁠13'priority_lowest ';

Reason: On many cases the 'server' is running on the same 'client' machine. One big query can "hold" the CPU on 100% for long seconds, even for minutes > making other operations impossible. :( /OFF It is a long long waited basic "feature". Saw many programmers to change to other RDBMS because of this problem. IMHO even a fast-dirty programming solution (like forcing sleep) is better than no solution.

[firebird-automations]

Commented by: PizzaProgram Ltd. (szakilaci)

/OFF Any Progress on this Issue ? PLEASE ! :(

[firebird-automations]

Commented by: PizzaProgram Ltd. (szakilaci)

/OFF still nothing ?

[firebird-automations]

Commented by: Desire Black (.des:.)

+1 for this. Setting priority per transaction should be essential! Waiting for this since ages too.

[firebird-automations]

Commented by: PizzaProgram Ltd. (szakilaci)

I've just realized: since FB v3.0 there is not possible any more to configure "wait time" in the firebird.conf file :( v2.1 and v2.5 had: UsePriorityScheduler = 1 PrioritySwitchDelay = 1000 #⁠ wait 1 sec before ... PriorityBoost = 10 #⁠ insert 10ms between every process > so the CPU has some time to "catch a breath" = run on 80% only

At FB v3.0 now there is only: ProcessPriorityLevel = 0 Witch is not so good because you can not wait a predefined time until priority should lower itself automatically.

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Also there is still no SLEEP(x milliseconds) function built in yet :( - it should provide a simple solution by inserting directly into SELECT or procedures/triggers. ... like here http://stackoverflow.com/a/5328416 similar to a "home-made" UDF function like SP_SLEEP: https://gist.github.com/pilcrow/873189 __________________________________________________

So this feature became a MUST NEED one. (Or at least the SLEEP() function.)

[firebird-automations]

Commented by: @hvlad

> Reason: > On many cases the 'server' is running on the same 'client' machine. One big query can "hold" the CPU on 100% for long seconds, even for minutes > making other operations impossible. :(

Is it still actual (considering almost no single-cpu\core present this days) ?

> It is a long long waited basic "feature". > Saw many programmers to change to other RDBMS because of this problem Really ? Basic "feature" ? Could you point me at such feature in other DBMS ?

[firebird-automations]

Commented by: PizzaProgram Ltd. (szakilaci)

> "Is it still actual (considering almost no single-cpu\core present this days) ? "

YESSS ! 1. Think about EEEPCs, Thin clients (touch-PCs), Tablets, etc. 2. Even a few seconds of delay on a quick-sale or restaurant environment can cause huge problems. 3. Usually the firebird.conf is configured to use ALL cores, if there are more than one > but even if just 1 core from 2 would block everything 1 minute long for 100%, while win-defender is using 100% on the other core = catastrophe. (I'm experiencing all these as real life, "everyday problems" on hundreds of machines. 20%-single core, 75%-dual core, 5% more.)

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It would be really really nice, if ALL 3 features would be possible:

1.) Put SLEEP(2) into long running selects or procedures

2.) handle priority on transactions OR on selects

3.) configure .conf files to handle it automatically, just like before at prev. versions.

[firebird-automations]

Commented by: PizzaProgram Ltd. (szakilaci)

Maybe possible to implement to Firebird 4.0+ ?