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pma: persistent file growth highpg tracking attempted fix

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spent a while debugging this, but there are still issues on restoration. We
cannot simply call _flist_new and _flist_record_alloc on persistent state
restoration since _flist_new won't properly set the highpg. If restoring, we
should derive the high flist page (alloced or not) from state->file_size_p. I
think I way overcomplicated this
This commit is contained in:
barter-simsum 2024-01-12 18:11:42 -05:00
parent 6a08d08c0f
commit aaa6f5e2ff
2 changed files with 21 additions and 7 deletions
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5
rust/ares_pma/c-src/btest.c
View File

@ -243,8 +243,9 @@ int main(int argc, char *argv[])
allocs[i].hi = allocs[i].lo + pages;
alloc_sizp += pages;
/* validate size changes to mlist and flist */
assert(_flist_sizep(state3->flist)
== (flist_sizp - alloc_sizp));
/* ;;: no longer a valid comparison since the flist may have grown */
/* assert(_flist_sizep(state3->flist) */
/* == (flist_sizp - alloc_sizp)); */
assert(_mlist_sizep(state3->mlist)
== (mlist_sizp - alloc_sizp));
N = _bt_numkeys(root);

23
rust/ares_pma/c-src/btree.c
View File

@ -331,7 +331,11 @@ struct BT_state {
BYTE *map;
BT_meta *meta_pages[2]; /* double buffered */
pgno_t file_size_p; /* the size of the pma file in pages */
pgno_t flist_highpg; /* highest page in the flist */
/* ;;: todo: this may be unnecessary. But it's tricky to derive the lo pgno to
insert into the flist when extending the file. Probably possible though
by accounting for both file_size_p and the size of all allocated node
partitions. */
pgno_t flist_highpg; /* highest page alloced or not (exclusive) */
unsigned int which; /* which double-buffered db are we using? */
BT_nlistnode *nlist; /* node freelist */
BT_mlistnode *mlist; /* memory freelist */
@ -537,6 +541,9 @@ _flist_record_alloc(BT_state *state, pgno_t lo, pgno_t hi)
free(*head);
*head = next;
}
/* update the highpg if necessary */
state->flist_highpg = MAX(state->flist_highpg, hi);
}
static BT_page *
@ -1578,11 +1585,15 @@ _mlist_new(BT_state *state)
return BT_SUCC;
}
/* ;;: todo: we could remove the hifreepg param if we can derive the highest
page (alloced or not) in the persistent file. */
static void
_flist_grow(BT_state *state, size_t pages)
_flist_grow(BT_state *state, size_t pages, pgno_t hifreepg)
/* grows the backing file by PMA_GROW_SIZE_p and appends this freespace to the
flist */
{
pgno_t flist_highpg = MAX(hifreepg, state->flist_highpg);
/* grow the backing file by at least PMA_GROW_SIZE_p */
pages = MAX(pages, PMA_GROW_SIZE_p);
off_t bytes = P2BYTES(pages);
@ -1594,8 +1605,8 @@ _flist_grow(BT_state *state, size_t pages)
/* and add this space to the flist */
_flist_insert(&state->flist,
state->flist_highpg,
state->flist_highpg + pages);
flist_highpg,
flist_highpg + pages);
state->flist_highpg += pages;
}
@ -2404,11 +2415,13 @@ _bt_falloc(BT_state *state, size_t pages)
contiguous space for pages */
start:
BT_flistnode **n = &state->flist;
pgno_t hifreepg = 0;
pgno_t ret = 0;
/* first fit */
for (; *n; n = &(*n)->next) {
size_t sz_p = (*n)->hi - (*n)->lo;
hifreepg = (*n)->hi;
if (sz_p >= pages) {
ret = (*n)->lo;
@ -2422,7 +2435,7 @@ _bt_falloc(BT_state *state, size_t pages)
/* flist out of mem, grow it */
DPRINTF("flist out of mem, growing current size (pages): 0x%" PRIX32 " to: 0x%" PRIX32,
state->file_size_p, state->file_size_p + PMA_GROW_SIZE_p);
_flist_grow(state, pages);
_flist_grow(state, pages, hifreepg);
/* restart the find procedure */
/* TODO: obv a minor optimization can be made here */
goto start;