revset: optimize "draft() & ::x" pattern
The `draft() & ::x` type query could be common for selecting one or more
draft feature branches being worked on.
Before this patch, `::x` may travel through the changelog DAG for a long
distance until it gets a smaller revision number than `min(draft())`. It
could be very slow on long changelog with distant (in terms of revision
numbers) drafts.
This patch adds a fast path for this situation, and will stop traveling the
changelog DAG once `::x` hits a non-draft revision.
The fast path also works for `secret()` and `not public()`.
To measure the performance difference, I used drawdag to create a repo that
emulates distant drafts:
DRAFT4
|
DRAFT3 # draft
/
PUBLIC9999 # public
|
PUBLIC9998
|
. DRAFT2
. |
. DRAFT1 # draft
| /
PUBLIC0001 # public
And measured the performance using the repo:
(BEFORE)
$ hg perfrevset 'draft() & ::(DRAFT2+DRAFT4)'
! wall 0.017132 comb 0.010000 user 0.010000 sys 0.000000 (best of 156)
$ hg perfrevset 'draft() & ::(all())'
! wall 0.024221 comb 0.030000 user 0.030000 sys 0.000000 (best of 113)
(AFTER)
$ hg perfrevset 'draft() & ::(DRAFT2+DRAFT4)'
! wall 0.000243 comb 0.000000 user 0.000000 sys 0.000000 (best of 9303)
$ hg perfrevset 'draft() & ::(all())'
! wall 0.004319 comb 0.000000 user 0.000000 sys 0.000000 (best of 655)
Differential Revision: https://phab.mercurial-scm.org/D441
HG = $(CURDIR)/../../hg
TARGET = chg
SRCS = chg.c hgclient.c procutil.c util.c
OBJS = $(SRCS:.c=.o)
CFLAGS ?= -O2 -Wall -Wextra -pedantic -g
CPPFLAGS ?= -D_FORTIFY_SOURCE=2 -D_GNU_SOURCE
override CFLAGS += -std=gnu99
ifdef HGPATH
override CPPFLAGS += -DHGPATH=\"$(HGPATH)\"
endif
DESTDIR =
PREFIX = /usr/local
MANDIR = $(PREFIX)/share/man/man1
CHGSOCKDIR = /tmp/chg$(shell id -u)
CHGSOCKNAME = $(CHGSOCKDIR)/server
.PHONY: all
all: $(TARGET)
$(TARGET): $(OBJS)
$(CC) $(LDFLAGS) -o $@ $(OBJS)
chg.o: hgclient.h procutil.h util.h
hgclient.o: hgclient.h procutil.h util.h
procutil.o: procutil.h util.h
util.o: util.h
.PHONY: install
install: $(TARGET)
install -d $(DESTDIR)$(PREFIX)/bin
install -m 755 $(TARGET) $(DESTDIR)$(PREFIX)/bin
install -d $(DESTDIR)$(MANDIR)
install -m 644 chg.1 $(DESTDIR)$(MANDIR)
.PHONY: serve
serve:
[ -d $(CHGSOCKDIR) ] || ( umask 077; mkdir $(CHGSOCKDIR) )
$(HG) serve --cwd / --cmdserver chgunix \
--address $(CHGSOCKNAME) \
--config cmdserver.log=/dev/stderr
.PHONY: clean
clean:
$(RM) $(OBJS)
.PHONY: distclean
distclean:
$(RM) $(OBJS) $(TARGET)