Re: Suggestion to add --continue-client-on-abort option to pgbench

On Fri, 26 Sep 2025 11:44:42 +0900
Yugo Nagata <nagata@sraoss.co.jp> wrote:

> On Thu, 25 Sep 2025 17:17:36 +0800
> Chao Li <li.evan.chao@gmail.com> wrote:
> 
> > Hi Yugo,
> > 
> > Thanks for the patch. After reviewing it, I got a few small comments:
> 
> Thank you for your reviewing and comments.
> 
> > > On Sep 25, 2025, at 15:22, Yugo Nagata <nagata@sraoss.co.jp> wrote:
> > > 
> > > -- 
> > > Yugo Nagata <nagata@sraoss.co.jp <mailto:nagata@sraoss.co.jp>>
> > > <v13-0003-Improve-error-messages-for-errors-that-cause-cli.patch><v13-0002-Add-continue-on-error-option.patch><v13-0001-Fix-assertion-failure-and-verbose-messages-in-pi.patch>
> > 
> > 
> > 1 - 0001
> > ```
> > @@ -3265,6 +3271,7 @@ readCommandResponse(CState *st, MetaCommand meta, char *varprefix)
> >  	PGresult   *res;
> >  	PGresult   *next_res;
> >  	int			qrynum = 0;
> > +	char	   *errmsg;
> > ```
> > 
> > I think we should initialize errmsg to NULL. Compiler won’t auto initialize a local variable. If it happens to not enter the while loop, then errmsg will hold a random value, then pg_free(errmsg) will have trouble.
> 
> I think this initialization is unnecessary, just like for res and next_res.
> If the code happens not to enter the while loop, pg_free(errmsg) will not be
> called anyway, since the error: label is only reachable from inside the loop.
> 
> > 2 - 0002
> > ```
> > +       <para>
> > +        Allows clients to continue their run even if an SQL statement fails due to
> > +        errors other than serialization or deadlock. Unlike serialization and deadlock
> > +        failures, clients do not retry the same transactions but start new transaction.
> > +        This option is useful when your custom script may raise errors due to some
> > +        reason like unique constraints violation. Without this option, the client is
> > +        aborted after such errors.
> > +       </para>
> > ```
> > 
> > A few nit suggestions:
> > 
> > * “continue their run” => “continue running”
> 
> Fixed.
> 
> > * “clients to not retry the same transactions but start new transaction” => “clients do not retry the same transaction but start a new transaction instead"
> 
> I see your point. Maybe we could follow Anthonin Bonnefoy's suggestion
> to use "proceed to the next transaction", as it may sound a bit more natural.
> 
> > * “due to some reason like” => “for reasons such as"
> 
> Fixed.
> 
> > 3 - 0002
> > ```
> > +	 * Without --continue-on-error:
> >  	 * failed (the number of failed transactions) =
> > ```
> > 
> > Maybe add an empty line after “without” line.
> 
> Makes sense. Fixed.
>  
> > 4 - 0002
> > ```
> > +	 * When --continue-on-error is specified:
> > +	 *
> > +	 * failed (number of failed transactions) =
> > ```
> > 
> > Maybe change to “With ---continue-on-error”, which sounds consistent with the previous “without”.
> 
> Fixed.
> 
> > 5 - 0002
> > ```
> > +	int64		other_sql_failures; /* number of failed transactions for
> > +									 * reasons other than
> > +									 * serialization/deadlock failure, which
> > +									 * is counted if --continue-on-error is
> > +									 * specified */
> > ```
> > 
> > How about rename this variable to “sql_errors”, which reflects to the new option name.
> 
> I think it’s better to keep the current name, since the variable counts failed transactions,
> even though that happens to be equivalent to the number of SQL errors. It’s also consistent
> with the other variables, serialization_failures and deadlock_failures.
> 
> > 6 - 0002
> > ```
> > @@ -4571,6 +4594,8 @@ getResultString(bool skipped, EStatus estatus)
> >  				return "serialization";
> >  			case ESTATUS_DEADLOCK_ERROR:
> >  				return "deadlock";
> > +			case ESTATUS_OTHER_SQL_ERROR:
> > +				return "other”;
> > ```
> > 
> > I think this can just return “error”. I checked where this function is called, there will not be other words such as “error” appended.
> 
> getResultString() is called to get a string that represents the type of error
> causing the transaction failure, so simply returning "error" doesn’t seem very
> useful.
>  
> > 7 - 0002
> > ```
> >  	/* it can be non-zero only if max_tries is not equal to one */
> > @@ -6569,6 +6602,10 @@ printResults(StatsData *total,
> >  							   sstats->deadlock_failures,
> >  							   (100.0 * sstats->deadlock_failures /
> >  								script_total_cnt));
> > +						printf(" - number of other failures: " INT64_FORMAT " (%.3f%%)\n",
> > +							   sstats->other_sql_failures,
> > +							   (100.0 * sstats->other_sql_failures /
> > +								script_total_cnt));
> > ```
> > 
> > Do we only want to print this number when “―continue-on-error” is given?
> 
> We could do that, but this message is printed only when
> --failures-detailed is specified. So I think users would not mind
> if it shows that the number of other failures is zero, even when
> --continue-on-error is not specified.
> 
> I would appreciate hearing other people's opinions on this.
> 
> 
> I've attached updated patches that include fixes for some of your
> suggestions and for Anthonin Bonnefoy's suggestion on the documentation.
> 
> I also split the patch according to Fujii-san's suggestion.

Fujii-san, thank you for committing the patch that fixes the assertion failure.
I've attached the remaining patches so that cfbot stays green.

Regards,
Yugo Nagata



-- 
Yugo Nagata <nagata@sraoss.co.jp>