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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Improving the isolationtester: fewer failures, less delay
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
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Andres Freund <andres@anarazel.de> writes:
> Only halfway related: I wonder if we should remove the automatic
> permutation stuff - it's practically never useful. Probably not worth
> changing...

Where it is useful, it saves a lot of error-prone typing ...

> Minor suggestion: I think the folliwing would be a bit easier to read if
> there first were a list of markers, and then separately the longer
> descriptions. Right now it's a bit hard to see which paragraph
> introduces a new type of marker, and which just adds further commentary.

OK, will do.  Will act on your other cosmetic points too, tomorrow or so.

>> +	if (step_has_blocker(pstep))
>> +	{
>> +		if (!(flags & STEP_RETRY))
>> +			printf("step %s: %s <waiting ...>\n",
>> +				   step->name, step->sql);
>> +		return true;
>> +	}

> Might be a bug in my mental state machine: Will this work correctly for
> PSB_ONCE, where we'll already returned before?

This bit ignores PSB_ONCE.  Once we've dropped out of try_complete_step
the first time, PSB_ONCE is done affecting things.  (I'm not in love
with that symbol name, if you have a better idea.)

			regards, tom lane