Hi,
While talking to Amit Kapila this morning, he mentioned to me that
there seem to be no CHECK_FOR_INTERRUPTS() calls anywhere in
heap_multi_insert() or the functions it calls. Should there be?
By way of contrast, heapgetpage() has this:
/* * Be sure to check for interrupts at least once per page. Checks at * higher code levels won't be able to
stopa seqscan that encounters many * pages' worth of consecutive dead tuples. */ CHECK_FOR_INTERRUPTS();
In heap_multi_insert(), we first do heap_prepare_insert() on each
tuple, which may involve dirtying many pages, since it handles TOAST.
Then, we loop over the tuples themselves and dirty a bunch more pages.
All of that will normally happen pretty quickly, but if the I/O
subsystem is very slow for some reason, such as due to heavy system
load, then it might take quite a long time. I'm thinking we might
want a CHECK_FOR_INTERRUPTS() in the following two places:
1. Inside toast_save_datum, at the top of the loop that starts with
"while (data_todo > 0)".
2. Inside heap_multi_insert, at the top of the loop that starts with
"while (ndone < ntuples)".
Thoughts?
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
