On Fri, 26 Sep 2008 17:10:44 -0400
Andrew Dunstan <[EMAIL PROTECTED]> wrote:

> Yes, there are several funny things going on, including some stuff
> with dependencies. I'll have a new patch tomorrow with luck. Thanks
> for testing.

O.k. I took at look at the patch itself and although I don't understand
all of it there were a couple of red flags to me:

+ if (ropt->create)
+               die_horribly(AH,modulename,
+                                        "parallel restore is
incompatible with --create\n");
+ 

This seems like an odd limitation. In my mind, the schema would not be
restored in parallel. The schema before data would restore as a single
thread. Even the largest schemas would only take minutes (if that).
Thus something like --create should never be a problem.

I also noticed you check if we have zlib? Is it even possible to use
the c format without it? (that would be new to me).

I noticed this line:


+       while((next_work_item = get_next_work_item(AH)) != NULL)
+       {
+               /* XXX need to improve this test in case there is no
table data */
+               /* need to test for indexes, FKs, PK, Unique, etc */
+               if(strcmp(next_work_item->desc,"TABLE DATA") == 0)
+                       break;
+               (void) _restore_one_te(AH, next_work_item, ropt,
false);
+ 
+               next_work_item->prestored = true;
+ 
+               _reduce_dependencies(AH,next_work_item);
+       }


Intead of the TABLE DATA compare, perhaps it makes sense to back patch
pg_dump to have a line delimiter in the TOC? That way even if there is
no TABLE DATA there would be a delimiter that says:

--- BEGIN TABLE DATA
--- END TABLE DATA

Thus if nothing is there... nothing is there?

+                       /* delay just long enough betweek forks to
give the catalog some
+                        * breathing space. Without this sleep I got 
+                        * "tuple concurrently updated" errors.
+                        */
+                       pg_usleep(500000);
+                       continue; /* in case the slots are not yet
full */
+               }

Could that be solved with a lock instead? Once the lock is released....

Anyway... just some thoughts. I apologize if I misunderstood the patch.

Sincerely,

Joshua D. Drake



> 
> cheers
> 
> andrew
> 


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