diff --git a/builtin-log.c b/builtin-log.c
index 8b2bf632c5..4e9d0cb69c 100644
--- a/builtin-log.c
+++ b/builtin-log.c
@@ -77,11 +77,78 @@ static void cmd_log_init(int argc, const char **argv, const char *prefix,
 	}
 }
 
+static void log_show_early(struct rev_info *revs, struct commit_list *list)
+{
+	int i = revs->early_output;
+
+	sort_in_topological_order(&list, revs->lifo);
+	while (list && i) {
+		struct commit *commit = list->item;
+		log_tree_commit(revs, commit);
+		list = list->next;
+		i--;
+	}
+}
+
+static void early_output(int signal)
+{
+	show_early_output = log_show_early;
+}
+
+static void setup_early_output(struct rev_info *rev)
+{
+	struct sigaction sa;
+	struct itimerval v;
+
+	/*
+	 * Set up the signal handler, minimally intrusively:
+	 * we only set a single volatile integer word (not
+	 * using sigatomic_t - trying to avoid unnecessary
+	 * system dependencies and headers), and using
+	 * SA_RESTART.
+	 */
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = early_output;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_RESTART;
+	sigaction(SIGALRM, &sa, NULL);
+
+	/*
+	 * If we can get the whole output in less than a
+	 * tenth of a second, don't even bother doing the
+	 * early-output thing..
+	 *
+	 * This is a one-time-only trigger.
+	 */
+	memset(&v, 0, sizeof(v));
+	v.it_value.tv_sec = 0;
+	v.it_value.tv_usec = 100000;
+	setitimer(ITIMER_REAL, &v, NULL);
+}
+
+static void finish_early_output(struct rev_info *rev)
+{
+	signal(SIGALRM, SIG_IGN);
+	if (rev->shown_one) {
+		rev->shown_one = 0;
+		if (rev->commit_format != CMIT_FMT_ONELINE)
+			putchar(rev->diffopt.line_termination);
+	}
+	printf("Final output:\n");
+}
+
 static int cmd_log_walk(struct rev_info *rev)
 {
 	struct commit *commit;
 
+	if (rev->early_output)
+		setup_early_output(rev);
+
 	prepare_revision_walk(rev);
+
+	if (rev->early_output)
+		finish_early_output(rev);
+
 	while ((commit = get_revision(rev)) != NULL) {
 		log_tree_commit(rev, commit);
 		if (!rev->reflog_info) {
diff --git a/revision.c b/revision.c
index e85b4af392..26610bb42d 100644
--- a/revision.c
+++ b/revision.c
@@ -10,6 +10,8 @@
 #include "reflog-walk.h"
 #include "patch-ids.h"
 
+volatile show_early_output_fn_t show_early_output;
+
 static char *path_name(struct name_path *path, const char *name)
 {
 	struct name_path *p;
@@ -533,6 +535,7 @@ static int limit_list(struct rev_info *revs)
 		struct commit_list *entry = list;
 		struct commit *commit = list->item;
 		struct object *obj = &commit->object;
+		show_early_output_fn_t show;
 
 		list = list->next;
 		free(entry);
@@ -550,6 +553,13 @@ static int limit_list(struct rev_info *revs)
 		if (revs->min_age != -1 && (commit->date > revs->min_age))
 			continue;
 		p = &commit_list_insert(commit, p)->next;
+
+		show = show_early_output;
+		if (!show)
+			continue;
+
+		show(revs, newlist);
+		show_early_output = NULL;
 	}
 	if (revs->cherry_pick)
 		cherry_pick_list(newlist, revs);
@@ -991,6 +1001,18 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
 				revs->topo_order = 1;
 				continue;
 			}
+			if (!prefixcmp(arg, "--early-output")) {
+				int count = 100;
+				switch (arg[14]) {
+				case '=':
+					count = atoi(arg+15);
+					/* Fallthrough */
+				case 0:
+					revs->topo_order = 1;
+					revs->early_output = count;
+					continue;
+				}
+			}
 			if (!strcmp(arg, "--parents")) {
 				revs->parents = 1;
 				continue;
diff --git a/revision.h b/revision.h
index 1f645764a5..d8a5a5021f 100644
--- a/revision.h
+++ b/revision.h
@@ -30,6 +30,8 @@ struct rev_info {
 	void *prune_data;
 	prune_fn_t *prune_fn;
 
+	unsigned int early_output;
+
 	/* Traversal flags */
 	unsigned int	dense:1,
 			no_merges:1,
@@ -105,6 +107,8 @@ struct rev_info {
 #define REV_TREE_DIFFERENT	2
 
 /* revision.c */
+typedef void (*show_early_output_fn_t)(struct rev_info *, struct commit_list *);
+volatile show_early_output_fn_t show_early_output;
 
 extern void init_revisions(struct rev_info *revs, const char *prefix);
 extern int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def);