Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> writes: > On Wed, Sep 20, 2017 at 4:25 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote: >> Yes. We don't allow out-of-line values, but we do allow compressed and >> short-header values.
> BTW, this comment looks still invalid for me...
>> #define SIGLENINT 4 /* >122 => key will *toast*, so very slow!!! */
I haven't done the math to see if 122 is exactly the right value, but at some point index_form_tuple would decide that the tuple was uncomfortably big and try to compress it. So the comment is right in general terms.