mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2026-07-05 06:46:11 +00:00
Code Activity

Parallel tactic (#9824) (#9825)

Browse source 
Add new parallel algorithm as a tactic (parallel_tactical2.cpp)
Don't port over old experiments from smt_parallel that we aren't using
(sls, inprocessing, failed_literal_mode for bb detection)
Fix bugs: lease cancellation/reslimit race condition, involves changing
lease epoch to simple boolean flag
Also, now there is a single shared set of params for the tactic and
smt_parallel

**Test runs for the parallel_tactical2 vs old smt_parallel version:**
run-2747-Z3-threads-4-qflia-30s-stats.md
run-2746-Z3-threads-4-qflia-30s-parallel_tactic-stats.md
run-2745-Z3-threads-1-qfbv-30s-stats.md
run-3013-Z3-threads-4-qfbv-30s-parallel_tactic-stats.md --> note this is
indeed run-3013, I reran after a bugfix in inc_sat_solver
run-2743-Z3-threads-4-qfnia-30s-stats.md
run-2742-Z3-threads-4-qfnia-30s-parallel_tactic-stats.md

**Test runs for the new smt_parallel with bugfixes:**
run-2801-Z3-threads-4-qflia-30s-smtparallel-bugfixes-stats.md,
run-2800-Z3-threads-4-qflia-30s-smtparallel-bugfixes-stats.md
run-2797-Z3-threads-4-qfnia-30s-smtparallel-bugfixes-stats.md
compare to old smt_parallel:
run-2747-Z3-threads-4-qflia-30s-stats.md
run-2743-Z3-threads-4-qfnia-30s-stats.md

Note that there is a slight regression on lia in run-2800. The source of
this appears to be the new new LP largest-cube LIA heuristic param,
which is enabled by default. disabling this param in run-2801 restored
performance (I didn't change this in this PR though, just something to
note)

http://mtzguido.tplinkdns.com:8081/z3/compare_stats.html

---------

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
Co-authored-by: Ilana Shapiro <ilanashapiro@Ilanas-MacBook-Pro.local>
Co-authored-by: Ilana Shapiro <ilanashapiro@Ilanas-MBP.localdomain>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
This commit is contained in:
Nikolaj Bjorner 2026-06-26 09:36:15 -07:00 • committed by GitHub
parent 15f33f458d
commit 612fab1c9a
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
29 changed files with 2694 additions and 1796 deletions
Download patch file Download diff file Expand all files Collapse all files

24
src/util/search_tree.h
View file

@ -50,7 +50,6 @@ namespace search_tree {
unsigned m_effort_spent = 0;
unsigned m_round_max_effort = 0;
unsigned m_active_workers = 0;
unsigned m_cancel_epoch = 0;
public:
node(literal const &l, node *parent) : m_literal(l), m_parent(parent), m_status(status::open) {}
@ -68,9 +67,17 @@ namespace search_tree {
literal const &get_literal() const {
return m_literal;
}
bool path_contains_atom(literal const& l) const {
for (node const* n = this; n; n = n->parent())
if (!Config::literal_is_null(n->get_literal()) && Config::same_atom(n->get_literal(), l))
return true;
return false;
}
void split(literal const &a, literal const &b) {
SASSERT(!Config::literal_is_null(a));
SASSERT(!Config::literal_is_null(b));
VERIFY(!path_contains_atom(a));
VERIFY(!path_contains_atom(b));
if (m_status != status::active)
return;
SASSERT(!m_left);
@ -148,12 +155,6 @@ namespace search_tree {
m_round_max_effort = effort;
m_effort_spent += m_round_max_effort;
}
unsigned get_cancel_epoch() const {
return m_cancel_epoch;
}
void inc_cancel_epoch() {
++m_cancel_epoch;
}
};
template <typename Config> class tree {
@ -340,7 +341,6 @@ namespace search_tree {
void close(node<Config> *n, vector<literal> const &C) {
if (!n || n->get_status() == status::closed)
return;
n->inc_cancel_epoch();
n->set_status(status::closed);
n->set_core(C);
close(n->left(), C);
@ -444,8 +444,8 @@ namespace search_tree {
// On timeout, either expand the current leaf or reopen the node for a
// later revisit, depending on the tree-expansion heuristic.
bool try_split(node<Config> *n, unsigned cancel_epoch, literal const &a, literal const &b, unsigned effort) {
if (is_lease_canceled(n, cancel_epoch))
bool try_split(node<Config> *n, literal const &a, literal const &b, unsigned effort) {
if (is_lease_canceled(n))
return false;
// Record at most one effort contribution per concurrent round on this node.
@ -544,8 +544,8 @@ namespace search_tree {
n->dec_active_workers();
}
bool is_lease_canceled(node<Config>* n, unsigned cancel_epoch) const {
return !n || n->get_status() == status::closed || n->get_cancel_epoch() != cancel_epoch;
bool is_lease_canceled(node<Config>* n) const {
return !n || n->get_status() == status::closed;
}
vector<literal> const &get_core_from_root() const {