tests/test-debugcommands.t
author Pierre-Yves David <pierre-yves.david@octobus.net>
Thu, 10 Oct 2019 03:49:33 +0200
changeset 43198 c16fe77e340a
parent 42712 cdf0e9523de1
child 44412 edc8504bc26b
permissions -rw-r--r--
pathcopies: give up any optimization based on `introrev` Between 8a0136f69027 and d98fb3f42f33, we sped up the search for the introduction revision during path copies. However, further checking show that finding the introduction revision is still expensive and that we are better off without it. So we simply drop it and only rely on the linkrev optimisation. I ran `perfpathcopies` on 6989 pair of revision in the pypy repository (`hg perfhelper-pathcopies`. The result is massively in favor of dropping this condition. The result of the copy tracing are unchanged. Attempt to use a smaller changes preserving linkrev usage were unsuccessful, it can return wrong result. The following changesets broke test-mv-cp-st-diff.t - if not f.isintroducedafter(limit): + if limit >= 0 and f.linkrev() < limit: return None Here are various numbers (before this changeset/after this changesets) source destination before after saved-time ratio worth cases e66f24650daf 695dfb0f493b 1.062843 1.246369 -0.183526 1.172675 c979853a3b6a 8d60fe293e79 1.036985 1.196414 -0.159429 1.153743 22349fa2fc33 fbb1c9fd86c0 0.879926 1.038682 -0.158756 1.180420 682b98f3e672 a4878080a536 0.909952 1.063801 -0.153849 1.169074 5adabc9b9848 920958a93997 0.993622 1.147452 -0.153830 1.154817 worse 1% dbfbfcf077e9 aea8f2fd3593 1.016595 1.082999 -0.066404 1.065320 worse 5% c95f1ced15f2 7d29d5e39734 0.453694 0.471156 -0.017462 1.038488 worse 10% 3e144ed1d5b7 2aef0e942480 0.035140 0.037535 -0.002395 1.068156 worse 25% 321fc60db035 801748ba582a 0.009267 0.009325 -0.000058 1.006259 median 2088ce763fc2 e6991321d78b 0.000665 0.000651 0.000014 0.978947 best 25% 915631a97de6 385b31354be6 0.040743 0.040363 0.000380 0.990673 best 10% ad495c36a765 19c10384d3e7 0.431658 0.411490 0.020168 0.953278 best 5% d13ae7d283ae 813c99f810ac 1.141404 1.075346 0.066058 0.942126 best 1% 81593cb4a496 99ae11866969 1.833297 0.063823 1.769474 0.034813 best cases c3b14617fbd7 743a0fcaa4eb 1101.811740 2.735970 1099.075770 0.002483 c3b14617fbd7 9ba6ab77fd29 1116.753953 2.800729 1113.953224 0.002508 058b99d6e81f 57e249b7a3ea 1246.128485 3.042762 1243.085723 0.002442 9a8c361aab49 0354a250d371 1253.111894 3.085796 1250.026098 0.002463 442dbbc53c68 3ec1002a818c 1261.786294 3.138607 1258.647687 0.002487 As one can see, the average case is not really impacted. However, the worth case we get after this changeset are much better than the one we had before it. We have 30 pairs where improvements are above 10 minutes. This reflect in the combined time for all pairs before: 26256s after: 1300s (-95%) If we remove these pathological 30 cases, we still see a significant improvements: before: 1631s after: 1245s (-24%)

  $ cat << EOF >> $HGRCPATH
  > [ui]
  > interactive=yes
  > EOF

  $ hg init debugrevlog
  $ cd debugrevlog
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ hg rm .
  removing a
  $ hg ci -Am make-it-empty
  $ hg revert --all -r 0
  adding a
  $ hg ci -Am make-it-full
#if reporevlogstore
  $ hg debugrevlog -c
  format : 1
  flags  : inline
  
  revisions     :   3
      merges    :   0 ( 0.00%)
      normal    :   3 (100.00%)
  revisions     :   3
      empty     :   0 ( 0.00%)
                     text  :   0 (100.00%)
                     delta :   0 (100.00%)
      snapshot  :   3 (100.00%)
        lvl-0   :         3 (100.00%)
      deltas    :   0 ( 0.00%)
  revision size : 191
      snapshot  : 191 (100.00%)
        lvl-0   :       191 (100.00%)
      deltas    :   0 ( 0.00%)
  
  chunks        :   3
      0x75 (u)  :   3 (100.00%)
  chunks size   : 191
      0x75 (u)  : 191 (100.00%)
  
  avg chain length  :  0
  max chain length  :  0
  max chain reach   : 67
  compression ratio :  0
  
  uncompressed data size (min/max/avg) : 57 / 66 / 62
  full revision size (min/max/avg)     : 58 / 67 / 63
  inter-snapshot size (min/max/avg)    : 0 / 0 / 0
  delta size (min/max/avg)             : 0 / 0 / 0
  $ hg debugrevlog -m
  format : 1
  flags  : inline, generaldelta
  
  revisions     :  3
      merges    :  0 ( 0.00%)
      normal    :  3 (100.00%)
  revisions     :  3
      empty     :  1 (33.33%)
                     text  :  1 (100.00%)
                     delta :  0 ( 0.00%)
      snapshot  :  2 (66.67%)
        lvl-0   :        2 (66.67%)
      deltas    :  0 ( 0.00%)
  revision size : 88
      snapshot  : 88 (100.00%)
        lvl-0   :       88 (100.00%)
      deltas    :  0 ( 0.00%)
  
  chunks        :  3
      empty     :  1 (33.33%)
      0x75 (u)  :  2 (66.67%)
  chunks size   : 88
      empty     :  0 ( 0.00%)
      0x75 (u)  : 88 (100.00%)
  
  avg chain length  :  0
  max chain length  :  0
  max chain reach   : 44
  compression ratio :  0
  
  uncompressed data size (min/max/avg) : 0 / 43 / 28
  full revision size (min/max/avg)     : 44 / 44 / 44
  inter-snapshot size (min/max/avg)    : 0 / 0 / 0
  delta size (min/max/avg)             : 0 / 0 / 0
  $ hg debugrevlog a
  format : 1
  flags  : inline, generaldelta
  
  revisions     : 1
      merges    : 0 ( 0.00%)
      normal    : 1 (100.00%)
  revisions     : 1
      empty     : 0 ( 0.00%)
                     text  : 0 (100.00%)
                     delta : 0 (100.00%)
      snapshot  : 1 (100.00%)
        lvl-0   :       1 (100.00%)
      deltas    : 0 ( 0.00%)
  revision size : 3
      snapshot  : 3 (100.00%)
        lvl-0   :       3 (100.00%)
      deltas    : 0 ( 0.00%)
  
  chunks        : 1
      0x75 (u)  : 1 (100.00%)
  chunks size   : 3
      0x75 (u)  : 3 (100.00%)
  
  avg chain length  : 0
  max chain length  : 0
  max chain reach   : 3
  compression ratio : 0
  
  uncompressed data size (min/max/avg) : 2 / 2 / 2
  full revision size (min/max/avg)     : 3 / 3 / 3
  inter-snapshot size (min/max/avg)    : 0 / 0 / 0
  delta size (min/max/avg)             : 0 / 0 / 0
#endif

Test debugindex, with and without the --verbose/--debug flag
  $ hg debugrevlogindex a
     rev linkrev nodeid       p1           p2
       0       0 b789fdd96dc2 000000000000 000000000000

#if no-reposimplestore
  $ hg --verbose debugrevlogindex a
     rev    offset  length linkrev nodeid       p1           p2
       0         0       3       0 b789fdd96dc2 000000000000 000000000000

  $ hg --debug debugrevlogindex a
     rev    offset  length linkrev nodeid                                   p1                                       p2
       0         0       3       0 b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000
#endif

  $ hg debugrevlogindex -f 1 a
     rev flag     size   link     p1     p2       nodeid
       0 0000        2      0     -1     -1 b789fdd96dc2

#if no-reposimplestore
  $ hg --verbose debugrevlogindex -f 1 a
     rev flag   offset   length     size   link     p1     p2       nodeid
       0 0000        0        3        2      0     -1     -1 b789fdd96dc2

  $ hg --debug debugrevlogindex -f 1 a
     rev flag   offset   length     size   link     p1     p2                                   nodeid
       0 0000        0        3        2      0     -1     -1 b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3
#endif

  $ hg debugindex -c
     rev linkrev nodeid       p1           p2
       0       0 07f494440405 000000000000 000000000000
       1       1 8cccb4b5fec2 07f494440405 000000000000
       2       2 b1e228c512c5 8cccb4b5fec2 000000000000
  $ hg debugindex -c --debug
     rev linkrev nodeid                                   p1                                       p2
       0       0 07f4944404050f47db2e5c5071e0e84e7a27bba9 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000
       1       1 8cccb4b5fec20cafeb99dd01c26d4dee8ea4388a 07f4944404050f47db2e5c5071e0e84e7a27bba9 0000000000000000000000000000000000000000
       2       2 b1e228c512c5d7066d70562ed839c3323a62d6d2 8cccb4b5fec20cafeb99dd01c26d4dee8ea4388a 0000000000000000000000000000000000000000
  $ hg debugindex -m
     rev linkrev nodeid       p1           p2
       0       0 a0c8bcbbb45c 000000000000 000000000000
       1       1 57faf8a737ae a0c8bcbbb45c 000000000000
       2       2 a35b10320954 57faf8a737ae 000000000000
  $ hg debugindex -m --debug
     rev linkrev nodeid                                   p1                                       p2
       0       0 a0c8bcbbb45c63b90b70ad007bf38961f64f2af0 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000
       1       1 57faf8a737ae7faf490582941a82319ba6529dca a0c8bcbbb45c63b90b70ad007bf38961f64f2af0 0000000000000000000000000000000000000000
       2       2 a35b103209548032201c16c7688cb2657f037a38 57faf8a737ae7faf490582941a82319ba6529dca 0000000000000000000000000000000000000000
  $ hg debugindex a
     rev linkrev nodeid       p1           p2
       0       0 b789fdd96dc2 000000000000 000000000000
  $ hg debugindex --debug a
     rev linkrev nodeid                                   p1                                       p2
       0       0 b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000

debugdelta chain basic output

#if reporevlogstore pure
  $ hg debugindexstats
  abort: debugindexstats only works with native code
  [255]
#endif
#if reporevlogstore no-pure
  $ hg debugindexstats
  node trie capacity: 4
  node trie count: 2
  node trie depth: 1
  node trie last rev scanned: -1
  node trie lookups: 4
  node trie misses: 1
  node trie splits: 1
  revs in memory: 3
#endif

#if reporevlogstore no-pure
  $ hg debugdeltachain -m
      rev  chain# chainlen     prev   delta       size    rawsize  chainsize     ratio   lindist extradist extraratio   readsize largestblk rddensity srchunks
        0       1        1       -1    base         44         43         44   1.02326        44         0    0.00000         44         44   1.00000        1
        1       2        1       -1    base          0          0          0   0.00000         0         0    0.00000          0          0   1.00000        1
        2       3        1       -1    base         44         43         44   1.02326        44         0    0.00000         44         44   1.00000        1

  $ hg debugdeltachain -m -T '{rev} {chainid} {chainlen}\n'
  0 1 1
  1 2 1
  2 3 1

  $ hg debugdeltachain -m -Tjson
  [
   {
    "chainid": 1,
    "chainlen": 1,
    "chainratio": 1.02325581395, (no-py3 !)
    "chainratio": 1.0232558139534884, (py3 !)
    "chainsize": 44,
    "compsize": 44,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0.0,
    "largestblock": 44,
    "lindist": 44,
    "prevrev": -1,
    "readdensity": 1.0,
    "readsize": 44,
    "rev": 0,
    "srchunks": 1,
    "uncompsize": 43
   },
   {
    "chainid": 2,
    "chainlen": 1,
    "chainratio": 0,
    "chainsize": 0,
    "compsize": 0,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0,
    "largestblock": 0,
    "lindist": 0,
    "prevrev": -1,
    "readdensity": 1,
    "readsize": 0,
    "rev": 1,
    "srchunks": 1,
    "uncompsize": 0
   },
   {
    "chainid": 3,
    "chainlen": 1,
    "chainratio": 1.02325581395, (no-py3 !)
    "chainratio": 1.0232558139534884, (py3 !)
    "chainsize": 44,
    "compsize": 44,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0.0,
    "largestblock": 44,
    "lindist": 44,
    "prevrev": -1,
    "readdensity": 1.0,
    "readsize": 44,
    "rev": 2,
    "srchunks": 1,
    "uncompsize": 43
   }
  ]

debugdelta chain with sparse read enabled

  $ cat >> $HGRCPATH <<EOF
  > [experimental]
  > sparse-read = True
  > EOF
  $ hg debugdeltachain -m
      rev  chain# chainlen     prev   delta       size    rawsize  chainsize     ratio   lindist extradist extraratio   readsize largestblk rddensity srchunks
        0       1        1       -1    base         44         43         44   1.02326        44         0    0.00000         44         44   1.00000        1
        1       2        1       -1    base          0          0          0   0.00000         0         0    0.00000          0          0   1.00000        1
        2       3        1       -1    base         44         43         44   1.02326        44         0    0.00000         44         44   1.00000        1

  $ hg debugdeltachain -m -T '{rev} {chainid} {chainlen} {readsize} {largestblock} {readdensity}\n'
  0 1 1 44 44 1.0
  1 2 1 0 0 1
  2 3 1 44 44 1.0

  $ hg debugdeltachain -m -Tjson
  [
   {
    "chainid": 1,
    "chainlen": 1,
    "chainratio": 1.02325581395, (no-py3 !)
    "chainratio": 1.0232558139534884, (py3 !)
    "chainsize": 44,
    "compsize": 44,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0.0,
    "largestblock": 44,
    "lindist": 44,
    "prevrev": -1,
    "readdensity": 1.0,
    "readsize": 44,
    "rev": 0,
    "srchunks": 1,
    "uncompsize": 43
   },
   {
    "chainid": 2,
    "chainlen": 1,
    "chainratio": 0,
    "chainsize": 0,
    "compsize": 0,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0,
    "largestblock": 0,
    "lindist": 0,
    "prevrev": -1,
    "readdensity": 1,
    "readsize": 0,
    "rev": 1,
    "srchunks": 1,
    "uncompsize": 0
   },
   {
    "chainid": 3,
    "chainlen": 1,
    "chainratio": 1.02325581395, (no-py3 !)
    "chainratio": 1.0232558139534884, (py3 !)
    "chainsize": 44,
    "compsize": 44,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0.0,
    "largestblock": 44,
    "lindist": 44,
    "prevrev": -1,
    "readdensity": 1.0,
    "readsize": 44,
    "rev": 2,
    "srchunks": 1,
    "uncompsize": 43
   }
  ]

  $ printf "This test checks things.\n" >> a
  $ hg ci -m a
  $ hg branch other
  marked working directory as branch other
  (branches are permanent and global, did you want a bookmark?)
  $ for i in `$TESTDIR/seq.py 5`; do
  >   printf "shorter ${i}" >> a
  >   hg ci -m "a other:$i"
  >   hg up -q default
  >   printf "for the branch default we want longer chains: ${i}" >> a
  >   hg ci -m "a default:$i"
  >   hg up -q other
  > done
  $ hg debugdeltachain a -T '{rev} {srchunks}\n' \
  >    --config experimental.sparse-read.density-threshold=0.50 \
  >    --config experimental.sparse-read.min-gap-size=0
  0 1
  1 1
  2 1
  3 1
  4 1
  5 1
  6 1
  7 1
  8 1
  9 1
  10 2
  11 1
  $ hg --config extensions.strip= strip --no-backup -r 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Test max chain len
  $ cat >> $HGRCPATH << EOF
  > [format]
  > maxchainlen=4
  > EOF

  $ printf "This test checks if maxchainlen config value is respected also it can serve as basic test for debugrevlog -d <file>.\n" >> a
  $ hg ci -m a
  $ printf "b\n" >> a
  $ hg ci -m a
  $ printf "c\n" >> a
  $ hg ci -m a
  $ printf "d\n" >> a
  $ hg ci -m a
  $ printf "e\n" >> a
  $ hg ci -m a
  $ printf "f\n" >> a
  $ hg ci -m a
  $ printf 'g\n' >> a
  $ hg ci -m a
  $ printf 'h\n' >> a
  $ hg ci -m a

  $ hg debugrevlog -d a
  # rev p1rev p2rev start   end deltastart base   p1   p2 rawsize totalsize compression heads chainlen
      0    -1    -1     0   ???          0    0    0    0     ???      ????           ?     1        0 (glob)
      1     0    -1   ???   ???          0    0    0    0     ???      ????           ?     1        1 (glob)
      2     1    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        2 (glob)
      3     2    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        3 (glob)
      4     3    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        4 (glob)
      5     4    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        0 (glob)
      6     5    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        1 (glob)
      7     6    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        2 (glob)
      8     7    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        3 (glob)
#endif

Test debuglocks command:

  $ hg debuglocks
  lock:  free
  wlock: free

* Test setting the lock

waitlock <file> will wait for file to be created. If it isn't in a reasonable
amount of time, displays error message and returns 1
  $ waitlock() {
  >     start=`date +%s`
  >     timeout=5
  >     while [ \( ! -f $1 \) -a \( ! -L $1 \) ]; do
  >         now=`date +%s`
  >         if [ "`expr $now - $start`" -gt $timeout ]; then
  >             echo "timeout: $1 was not created in $timeout seconds"
  >             return 1
  >         fi
  >         sleep 0.1
  >     done
  > }
  $ dolock() {
  >     {
  >         waitlock .hg/unlock
  >         rm -f .hg/unlock
  >         echo y
  >     } | hg debuglocks "$@" > /dev/null
  > }
  $ dolock -s &
  $ waitlock .hg/store/lock

  $ hg debuglocks
  lock:  user *, process * (*s) (glob)
  wlock: free
  [1]
  $ touch .hg/unlock
  $ wait
  $ [ -f .hg/store/lock ] || echo "There is no lock"
  There is no lock

* Test setting the wlock

  $ dolock -S &
  $ waitlock .hg/wlock

  $ hg debuglocks
  lock:  free
  wlock: user *, process * (*s) (glob)
  [1]
  $ touch .hg/unlock
  $ wait
  $ [ -f .hg/wlock ] || echo "There is no wlock"
  There is no wlock

* Test setting both locks

  $ dolock -Ss &
  $ waitlock .hg/wlock && waitlock .hg/store/lock

  $ hg debuglocks
  lock:  user *, process * (*s) (glob)
  wlock: user *, process * (*s) (glob)
  [2]

* Test failing to set a lock

  $ hg debuglocks -s
  abort: lock is already held
  [255]

  $ hg debuglocks -S
  abort: wlock is already held
  [255]

  $ touch .hg/unlock
  $ wait

  $ hg debuglocks
  lock:  free
  wlock: free

* Test forcing the lock

  $ dolock -s &
  $ waitlock .hg/store/lock

  $ hg debuglocks
  lock:  user *, process * (*s) (glob)
  wlock: free
  [1]

  $ hg debuglocks -L

  $ hg debuglocks
  lock:  free
  wlock: free

  $ touch .hg/unlock
  $ wait

* Test forcing the wlock

  $ dolock -S &
  $ waitlock .hg/wlock

  $ hg debuglocks
  lock:  free
  wlock: user *, process * (*s) (glob)
  [1]

  $ hg debuglocks -W

  $ hg debuglocks
  lock:  free
  wlock: free

  $ touch .hg/unlock
  $ wait

Test WdirUnsupported exception

  $ hg debugdata -c ffffffffffffffffffffffffffffffffffffffff
  abort: working directory revision cannot be specified
  [255]

Test cache warming command

  $ rm -rf .hg/cache/
  $ hg debugupdatecaches --debug
  updating the branch cache
  $ ls -r .hg/cache/*
  .hg/cache/tags2-served
  .hg/cache/tags2
  .hg/cache/rbc-revs-v1
  .hg/cache/rbc-names-v1
  .hg/cache/hgtagsfnodes1
  .hg/cache/branch2-visible-hidden
  .hg/cache/branch2-visible
  .hg/cache/branch2-served.hidden
  .hg/cache/branch2-served
  .hg/cache/branch2-immutable
  .hg/cache/branch2-base

Test debugcolor

#if no-windows
  $ hg debugcolor --style --color always | egrep 'mode|style|log\.'
  color mode: 'ansi'
  available style:
  \x1b[0;33mlog.changeset\x1b[0m:                      \x1b[0;33myellow\x1b[0m (esc)
#endif

  $ hg debugcolor --style --color never
  color mode: None
  available style:

  $ cd ..

Test internal debugstacktrace command

  $ cat > debugstacktrace.py << EOF
  > from __future__ import absolute_import
  > from mercurial import (
  >     pycompat,
  >     util,
  > )
  > def f():
  >     util.debugstacktrace(f=pycompat.stdout)
  >     g()
  > def g():
  >     util.dst(b'hello from g\\n', skip=1)
  >     h()
  > def h():
  >     util.dst(b'hi ...\\nfrom h hidden in g', 1, depth=2)
  > f()
  > EOF
  $ "$PYTHON" debugstacktrace.py
  stacktrace at:
   debugstacktrace.py:14 in * (glob)
   debugstacktrace.py:7  in f
  hello from g at:
   debugstacktrace.py:14 in * (glob)
   debugstacktrace.py:8  in f
  hi ...
  from h hidden in g at:
   debugstacktrace.py:8  in f
   debugstacktrace.py:11 in g

Test debugcapabilities command:

  $ hg debugcapabilities ./debugrevlog/
  Main capabilities:
    branchmap
    $USUAL_BUNDLE2_CAPS$
    getbundle
    known
    lookup
    pushkey
    unbundle
  Bundle2 capabilities:
    HG20
    bookmarks
    changegroup
      01
      02
    digests
      md5
      sha1
      sha512
    error
      abort
      unsupportedcontent
      pushraced
      pushkey
    hgtagsfnodes
    listkeys
    phases
      heads
    pushkey
    remote-changegroup
      http
      https
    rev-branch-cache
    stream
      v2

Test debugpeer

  $ hg --config ui.ssh="\"$PYTHON\" \"$TESTDIR/dummyssh\"" debugpeer ssh://user@dummy/debugrevlog
  url: ssh://user@dummy/debugrevlog
  local: no
  pushable: yes

  $ hg --config ui.ssh="\"$PYTHON\" \"$TESTDIR/dummyssh\"" --debug debugpeer ssh://user@dummy/debugrevlog
  running "*" "*/tests/dummyssh" 'user@dummy' 'hg -R debugrevlog serve --stdio' (glob) (no-windows !)
  running "*" "*\tests/dummyssh" "user@dummy" "hg -R debugrevlog serve --stdio" (glob) (windows !)
  devel-peer-request: hello+between
  devel-peer-request:   pairs: 81 bytes
  sending hello command
  sending between command
  remote: 440
  remote: capabilities: batch branchmap $USUAL_BUNDLE2_CAPS$ changegroupsubset getbundle known lookup protocaps pushkey streamreqs=generaldelta,revlogv1,sparserevlog unbundle=HG10GZ,HG10BZ,HG10UN unbundlehash
  remote: 1
  devel-peer-request: protocaps
  devel-peer-request:   caps: * bytes (glob)
  sending protocaps command
  url: ssh://user@dummy/debugrevlog
  local: no
  pushable: yes