I believe it is 8k to match the base size for the filesystem block size,
for performance.
>
> I just wrote about issues regarding upping the max blocksize. There is
> stuff in storage/itemid.h that would need to be modified (also in
> bufmgr.h, but that is trivial). Th idea is that:
>
> typedef struct ItemIdData
> {
> /* line pointers */
> unsigned lp_off:13, /* offset to find tup */
> /* can be reduced by 2 if necc. */
> lp_flags:6, /* flags on tuple */
> lp_len:13; /* length of
> tuple */
> } ItemIdData;
>
> the ItemIdData.lp_len is maxed at 2^13, or 8192. My query then is:
> which of the items is it saying 'can be reduced by 2 if necc'? For, if
> that is accurate, I'd like to e.g. lp_off:11 and lp_len:15, allowing for
> tuples of 32768 or something. And also not breaking the nice 32 bit
> length of the struct.
>
> Lemme know...
>
> ps. why not allow for larger tuples in general? Do we take a speed hit?
>
>
- --
Bruce Momjian
maillist@candle.pha.pa.us
------------------------------
