Commit graph

868 commits

Author SHA1 Message Date
Brian Goff
93ac040bf0 Lock down docker root dir perms.
Do not use 0701 perms.
0701 dir perms allows anyone to traverse the docker dir.
It happens to allow any user to execute, as an example, suid binaries
from image rootfs dirs because it allows traversal AND critically
container users need to be able to do execute things.

0701 on lower directories also happens to allow any user to modify
     things in, for instance, the overlay upper dir which neccessarily
     has 0755 permissions.

This changes to use 0710 which allows users in the group to traverse.
In userns mode the UID owner is (real) root and the GID is the remapped
root's GID.

This prevents anyone but the remapped root to traverse our directories
(which is required for userns with runc).

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
(cherry picked from commit ef7237442147441a7cadcda0600be1186d81ac73)
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2021-08-19 20:40:15 +00:00
Brian Goff
df2a989769
Add shim config for custom runtimes for plugins
This fixes a panic when an admin specifies a custom default runtime,
when a plugin is started the shim config is nil.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
(cherry picked from commit 2903863a1d)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2021-02-17 21:20:03 +01:00
Brian Goff
e908cc3901 Use real root with 0701 perms
Various dirs in /var/lib/docker contain data that needs to be mounted
into a container. For this reason, these dirs are set to be owned by the
remapped root user, otherwise there can be permissions issues.
However, this uneccessarily exposes these dirs to an unprivileged user
on the host.

Instead, set the ownership of these dirs to the real root (or rather the
UID/GID of dockerd) with 0701 permissions, which allows the remapped
root to enter the directories but not read/write to them.
The remapped root needs to enter these dirs so the container's rootfs
can be configured... e.g. to mount /etc/resolve.conf.

This prevents an unprivileged user from having read/write access to
these dirs on the host.
The flip side of this is now any user can enter these directories.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2021-01-26 17:23:32 +00:00
Brian Goff
bfedd27259 Do not set DOCKER_TMP to be owned by remapped root
The remapped root does not need access to this dir.
Having this owned by the remapped root opens the host up to an
uprivileged user on the host being able to escalate privileges.

While it would not be normal for the remapped UID to be used outside of
the container context, it could happen.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2021-01-26 17:23:32 +00:00
Brian Goff
4a175fd050 Cleanup container shutdown check and add test
Adds a test case for the case where dockerd gets stuck on startup due to
hanging `daemon.shutdownContainer`

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2020-12-23 16:59:03 +00:00
Simon Ferquel
af0665861b Fix a potential hang when starting after a non-clean shutdown
Previous startup sequence used to call "containerStop" on containers that were persisted with a running state but are not alive when restarting (can happen on non-clean shutdown).
This call was made before fixing-up the RunningState of the container, and tricked the daemon to trying to kill a non-existing process and ultimately hang.

The fix is very simple - just add a condition on calling containerStop.

Signed-off-by: Simon Ferquel <simon.ferquel@docker.com>
2020-12-18 10:20:56 +01:00
Sebastiaan van Stijn
7e600eaae0
daemon: improve log messages during startup / shutdown
Consistently set "container ID" as a field for log messages, so that
logs can be associated with a container.

With this logs look like;

    INFO[2020-12-15T12:30:46.239329903Z] Loading containers: start.
    DEBU[2020-12-15T12:30:46.239919357Z] processing event stream      module=libcontainerd namespace=moby
    DEBU[2020-12-15T12:30:46.242061458Z] loaded container             container=622dec5f737d532da347bc627655ebc351fa5887476e8b8c33e5fbc5d0e48b5c paused=false running=false
    DEBU[2020-12-15T12:30:46.242185251Z] loaded container             container=47f348160645f46a17c758d120dec600967eed4adf08dd28b809725971d062cc paused=false running=false
    DEBU[2020-12-15T12:30:46.242912375Z] loaded container             container=e29c34c14b84810bc1e6cb6978a81e863601bfbe9ffe076c07dd5f6a439289d6 paused=false running=false
    DEBU[2020-12-15T12:30:46.243165260Z] loaded container             container=31d40ee3e591a50ebee790b08c2bec751610d2eca51ca1a371ea1ff66ea46c1d paused=false running=false
    DEBU[2020-12-15T12:30:46.243585164Z] loaded container             container=03dd5b1dc251a12d2e74eb54cb3ace66c437db228238a8d4831a264c9313c192 paused=false running=false
    DEBU[2020-12-15T12:30:46.244870764Z] loaded container             container=b774141975cc511cc61fc5f374793503bb2e8fa774d6580ac47111a089de1b9b paused=false running=false
    DEBU[2020-12-15T12:30:46.245140276Z] loaded container             container=b8a7229824fb84ff6f5af537a8ba987d106bf9a24a9aad3b628605d26b3facc4 paused=false running=false
    DEBU[2020-12-15T12:30:46.245457025Z] loaded container             container=b3256ff87fc6f243d9e044fb3d7988ef61c86bfb957d90c0227e8a9697ffa49c paused=false running=false
    DEBU[2020-12-15T12:30:46.292515417Z] restoring container          container=b3256ff87fc6f243d9e044fb3d7988ef61c86bfb957d90c0227e8a9697ffa49c paused=false running=false
    DEBU[2020-12-15T12:30:46.292612379Z] restoring container          container=31d40ee3e591a50ebee790b08c2bec751610d2eca51ca1a371ea1ff66ea46c1d paused=false running=false
    DEBU[2020-12-15T12:30:46.292573767Z] restoring container          container=b8a7229824fb84ff6f5af537a8ba987d106bf9a24a9aad3b628605d26b3facc4 paused=false running=false
    DEBU[2020-12-15T12:30:46.292602437Z] restoring container          container=b774141975cc511cc61fc5f374793503bb2e8fa774d6580ac47111a089de1b9b paused=false running=false
    DEBU[2020-12-15T12:30:46.305032730Z] restoring container          container=47f348160645f46a17c758d120dec600967eed4adf08dd28b809725971d062cc paused=false running=false
    DEBU[2020-12-15T12:30:46.305421360Z] restoring container          container=622dec5f737d532da347bc627655ebc351fa5887476e8b8c33e5fbc5d0e48b5c paused=false running=false
    DEBU[2020-12-15T12:30:46.305558773Z] restoring container          container=03dd5b1dc251a12d2e74eb54cb3ace66c437db228238a8d4831a264c9313c192 paused=false running=false
    DEBU[2020-12-15T12:30:46.307662990Z] restoring container          container=e29c34c14b84810bc1e6cb6978a81e863601bfbe9ffe076c07dd5f6a439289d6 paused=false running=false
    ...
    INFO[2020-12-15T12:30:46.536506204Z] Loading containers: done.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2020-12-15 15:57:39 +01:00
Brian Goff
9ca3bb632e Store image manifests in containerd content store
This allows us to cache manifests and avoid extra round trips to the
registry for content we already know about.

dockerd currently does not support containerd on Windows, so this does
not store manifests on Windows, yet.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2020-11-05 20:02:18 +00:00
Sebastiaan van Stijn
5ca758199d
replace pkg/locker with github.com/moby/locker
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2020-09-10 22:15:40 +02:00
Brian Goff
f63f73a4a8 Configure shims from runtime config
In dockerd we already have a concept of a "runtime", which specifies the
OCI runtime to use (e.g. runc).
This PR extends that config to add containerd shim configuration.
This option is only exposed within the daemon itself (cannot be
configured in daemon.json).
This is due to issues in supporting unknown shims which will require
more design work.

What this change allows us to do is keep all the runtime config in one
place.

So the default "runc" runtime will just have it's already existing shim
config codified within the runtime config alone.
I've also added 2 more "stock" runtimes which are basically runc+shimv1
and runc+shimv2.
These new runtime configurations are:

- io.containerd.runtime.v1.linux - runc + v1 shim using the V1 shim API
- io.containerd.runc.v2 - runc + shim v2

These names coincide with the actual names of the containerd shims.

This allows the user to essentially control what shim is going to be
used by either specifying these as a `--runtime` on container create or
by setting `--default-runtime` on the daemon.

For custom/user-specified runtimes, the default shim config (currently
shim v1) is used.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2020-07-13 14:18:02 -07:00
Sebastiaan van Stijn
4534a7afc3
daemon: use containerd/sys to detect UserNamespaces
The implementation in libcontainer/system is quite complicated,
and we only use it to detect if user-namespaces are enabled.

In addition, the implementation in containerd uses a sync.Once,
so that detection (and reading/parsing `/proc/self/uid_map`) is
only performed once.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2020-06-15 13:06:08 +02:00
Tonis Tiigi
fdb71e410c registry: fix mtls config dir passing
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
2020-05-14 12:02:09 -07:00
Akihiro Suda
f350b53241 cgroup2: implement docker info
ref: https://www.kernel.org/doc/html/latest/admin-guide/cgroup-v2.html

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
2020-04-17 07:20:01 +09:00
Sebastiaan van Stijn
db669cd117
Merge pull request #40814 from tonistiigi/buildkit-update
vendor: update buildkit to ae7ff174
2020-04-15 21:18:51 +02:00
Akihiro Suda
2e5923c547
Merge pull request #39705 from thaJeztah/daemon_nits
daemon: various nits and small fixes
2020-04-15 09:11:25 +09:00
Tonis Tiigi
0cdf6ba9c8 vendor: update buildkit to ae7ff174
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
2020-04-14 08:26:07 -07:00
Sebastiaan van Stijn
eb14d936bf
daemon: rename variables that collide with imported package names
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2020-04-14 17:22:23 +02:00
Brian Goff
ced91bee4b On startup, actually shutdown the container.
When a container is left running after the daemon exits (e.g. the daemon
is SIGKILL'd or crashes), it should stop any running containers when the
daemon starts back up.

What actually happens is the daemon only sends the container's
configured stop signal and does not check if it has exited.
If the container does not actually exit then it is left running.

This fixes this unexpected behavior by calling the same function to shut
down the container that the daemon shutdown process does.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2020-04-13 14:20:12 -07:00
Akihiro Suda
f073ed4187
Merge pull request #39816 from tao12345666333/rm-systeminfo-error-handler
Remove `SystemInfo()` error handling.
2020-03-13 01:59:13 +09:00
Akihiro Suda
9a82a9a8ea vendor containerd, BuildKit, protobuf, grpc, and golang.org/x
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
2020-03-03 10:25:20 +09:00
Brian Goff
62bd5a33f7
Merge pull request #40137 from fuweid/me-wait-for-remote-containerd-before-reload
daemon: add grpc.WithBlock option
2020-02-21 10:11:10 -08:00
Akihiro Suda
612343618d cgroup2: use shim V2
* Requires containerd binaries from containerd/containerd#3799 . Metrics are unimplemented yet.
* Works with crun v0.10.4, but `--security-opt seccomp=unconfined` is needed unless using master version of libseccomp
  ( containers/crun#156, seccomp/libseccomp#177 )
* Doesn't work with master runc yet
* Resource limitations are unimplemented

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
2020-01-01 02:58:40 +09:00
Brian Goff
47c5c67ed8
Merge pull request #40032 from jmartin84/fix-grpc-withdialer-deprecation-warning
Fix grpc withdialer deprecation warning
2019-11-05 12:20:33 -08:00
Wei Fu
9f73396dab daemon: add grpc.WithBlock option
WithBlock makes sure that the following containerd request is reliable.

In one edge case with high load pressure, kernel kills dockerd, containerd
and containerd-shims caused by OOM. When both dockerd and containerd
restart, but containerd will take time to recover all the existing
containers. Before containerd serving, dockerd will failed with gRPC
error. That bad thing is that restore action will still ignore the
any non-NotFound errors and returns running state for
already stopped container. It is unexpected behavior. And
we need to restart dockerd to make sure that anything is OK.

It is painful. Add WithBlock can prevent the edge case. And
n common case, the containerd will be serving in shortly.
It is not harm to add WithBlock for containerd connection.

Signed-off-by: Wei Fu <fuweid89@gmail.com>
2019-10-25 12:19:35 +08:00
Sebastiaan van Stijn
05469b5fa2
daemon: add "isWindows" const
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-10-17 23:49:43 +02:00
Justen Martin
3b49bd1d84
replaced call to deprecated grpc method WithDialer with WithContextDialer
Signed-off-by: Justen Martin <jmart@the-coder.com>
2019-10-10 15:34:42 -05:00
Derek McGowan
bc5484d2dd
bump moby/buildkit f7042823e340d38d1746aa675b83d1aca431cee3
full diff: 588c73e1e4...f7042823e3

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

fix daemon for changes in containerd registry configuration

Signed-off-by: Evan Hazlett <ejhazlett@gmail.com>

Update buildernext and daemon for buildkit update

Signed-off-by: Derek McGowan <derek@mcgstyle.net>
2019-10-04 15:05:35 -07:00
Lukas Heeren
ce61a1ed98
Adding ability to change max download attempts
Moby works perfectly when you are in a situation when one has a good and stable
internet connection. Operating in area's where internet connectivity is likely
to be lost in undetermined intervals, like a satellite connection or 4G/LTE in
rural area's, can become a problem when pulling a new image. When connection is
lost while image layers are being pulled, Moby will try to reconnect up to 5 times.
If this fails, the incompletely downloaded layers are lost will need to be completely
downloaded again during the next pull request. This means that we are using more
data than we might have to.

Pulling a layer multiple times from the start can become costly over a satellite
or 4G/LTE connection. As these techniques (especially 4G) quite common in IoT and
Moby is used to run Azure IoT Edge devices, I would like to add a settable maximum
download attempts. The maximum download attempts is currently set at 5
(distribution/xfer/download.go). I would like to change this constant to a variable
that the user can set. The default will still be 5, so nothing will change from
the current version unless specified when starting the daemon with the added flag
or in the config file.

I added a default value of 5 for DefaultMaxDownloadAttempts and a settable
max-download-attempts in the daemon config file. It is also added to the config
of dockerd so it can be set with a flag when starting the daemon. This value gets
stored in the imageService of the daemon when it is initiated and can be passed
to the NewLayerDownloadManager as a parameter. It will be stored in the
LayerDownloadManager when initiated. This enables us to set the max amount of
retries in makeDownoadFunc equal to the max download attempts.

I also added some tests that are based on maxConcurrentDownloads/maxConcurrentUploads.

You can pull this version and test in a development container. Either create a config
`file /etc/docker/daemon.json` with `{"max-download-attempts"=3}``, or use
`dockerd --max-download-attempts=3 -D &` to start up the dockerd. Start downloading
a container and disconnect from the internet whilst downloading. The result would
be that it stops pulling after three attempts.

Signed-off-by: Lukas Heeren <lukas-heeren@hotmail.com>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-09-19 13:51:40 +02:00
Jintao Zhang
9134130b39 Remove SystemInfo() error handling.
Signed-off-by: Jintao Zhang <zhangjintao9020@gmail.com>
2019-08-29 07:44:39 +08:00
Tibor Vass
32688a47f3
Merge pull request #39699 from thaJeztah/mkdirall_dropin
Allow system.MkDirAll() to be used as drop-in for os.MkDirAll()
2019-08-27 16:27:53 -07:00
Deep Debroy
4d5b6260bc Fix regression in handling of NotFound err during startup
Signed-off-by: Deep Debroy <ddebroy@docker.com>
2019-08-08 16:58:52 -07:00
Sebastiaan van Stijn
e554ab5589
Allow system.MkDirAll() to be used as drop-in for os.MkDirAll()
also renamed the non-windows variant of this file to be
consistent with other files in this package

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-08-08 15:05:49 +02:00
Sebastiaan van Stijn
bad0b4e604
Remove skip evaluation of symlinks to data root on IoT Core
This fix was added in 8e71b1e210 to work around
a go issue (https://github.com/golang/go/issues/20506).

That issue was fixed in
66c03d39f3,
which is part of Go 1.10 and up. This reverts the changes that were made in
8e71b1e210, and are no longer needed.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-07-13 23:44:51 +02:00
Brian Goff
24ad2f486d Add (hidden) flags to set containerd namespaces
This allows our tests, which all share a containerd instance, to be a
bit more isolated by setting the containerd namespaces to the generated
daemon ID's rather than the default namespaces.

This came about because I found in some cases we had test daemons
failing to start (really very slow to start) because it was (seemingly)
processing events from other tests.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2019-07-11 17:27:48 -07:00
Tibor Vass
f695e98cb7 Revert "Remove the rest of v1 manifest support"
This reverts commit 98fc09128b in order to
keep registry v2 schema1 handling and libtrust-key-based engine ID.

Because registry v2 schema1 was not officially deprecated and
registries are still relying on it, this patch puts its logic back.

However, registry v1 relics are not added back since v1 logic has been
removed a while ago.

This also fixes an engine upgrade issue in a swarm cluster. It was relying
on the Engine ID to be the same upon upgrade, but the mentioned commit
modified the logic to use UUID and from a different file.

Since the libtrust key is always needed to support v2 schema1 pushes,
that the old engine ID is based on the libtrust key, and that the engine ID
needs to be conserved across upgrades, adding a UUID-based engine ID logic
seems to add more complexity than it solves the problems.

Hence reverting the engine ID changes as well.

Signed-off-by: Tibor Vass <tibor@docker.com>
2019-06-18 00:36:01 +00:00
Sebastiaan van Stijn
28678f2226
Merge pull request #38349 from wk8/wk8/os_version
Adding OS version info to nodes' `Info` struct and to the system info's API
2019-06-07 14:54:51 +02:00
Sebastiaan van Stijn
c85fe2d224
Merge pull request #38522 from cpuguy83/fix_timers
Make sure timers are stopped after use.
2019-06-07 13:16:46 +02:00
Jean Rouge
d363a1881e Adding OS version info to the nodes' Info struct
This is needed so that we can add OS version constraints in Swarmkit, which
does require the engine to report its host's OS version (see
https://github.com/docker/swarmkit/issues/2770).

The OS version is parsed from the `os-release` file on Linux, and from the
`ReleaseId` string value of the `SOFTWARE\Microsoft\Windows NT\CurrentVersion`
registry key on Windows.

Added unit tests when possible, as well as Prometheus metrics.

Signed-off-by: Jean Rouge <rougej+github@gmail.com>
2019-06-06 22:40:10 +00:00
Michael Crosby
b9b5dc37e3 Remove inmemory container map
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
2019-04-05 15:48:07 -04:00
Michael Crosby
45e328b0ac Remove libcontainerd status type
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
2019-04-04 15:17:13 -04:00
Tonis Tiigi
1a0f04e08e daemon: fix mirrors validation
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
2019-04-02 11:38:21 -07:00
John Howard
a3eda72f71
Merge pull request #38541 from Microsoft/jjh/containerd
Windows: Experimental: ContainerD runtime
2019-03-19 21:09:19 -07:00
John Howard
85ad4b16c1 Windows: Experimental: Allow containerd for runtime
Signed-off-by: John Howard <jhoward@microsoft.com>

This is the first step in refactoring moby (dockerd) to use containerd on Windows.
Similar to the current model in Linux, this adds the option to enable it for runtime.
It does not switch the graphdriver to containerd snapshotters.

 - Refactors libcontainerd to a series of subpackages so that either a
  "local" containerd (1) or a "remote" (2) containerd can be loaded as opposed
  to conditional compile as "local" for Windows and "remote" for Linux.

 - Updates libcontainerd such that Windows has an option to allow the use of a
   "remote" containerd. Here, it communicates over a named pipe using GRPC.
   This is currently guarded behind the experimental flag, an environment variable,
   and the providing of a pipename to connect to containerd.

 - Infrastructure pieces such as under pkg/system to have helper functions for
   determining whether containerd is being used.

(1) "local" containerd is what the daemon on Windows has used since inception.
It's not really containerd at all - it's simply local invocation of HCS APIs
directly in-process from the daemon through the Microsoft/hcsshim library.

(2) "remote" containerd is what docker on Linux uses for it's runtime. It means
that there is a separate containerd service running, and docker communicates over
GRPC to it.

To try this out, you will need to start with something like the following:

Window 1:
	containerd --log-level debug

Window 2:
	$env:DOCKER_WINDOWS_CONTAINERD=1
	dockerd --experimental -D --containerd \\.\pipe\containerd-containerd

You will need the following binary from github.com/containerd/containerd in your path:
 - containerd.exe

You will need the following binaries from github.com/Microsoft/hcsshim in your path:
 - runhcs.exe
 - containerd-shim-runhcs-v1.exe

For LCOW, it will require and initrd.img and kernel in `C:\Program Files\Linux Containers`.
This is no different to the current requirements. However, you may need updated binaries,
particularly initrd.img built from Microsoft/opengcs as (at the time of writing), Linuxkit
binaries are somewhat out of date.

Note that containerd and hcsshim for HCS v2 APIs do not yet support all the required
functionality needed for docker. This will come in time - this is a baby (although large)
step to migrating Docker on Windows to containerd.

Note that the HCS v2 APIs are only called on RS5+ builds. RS1..RS4 will still use
HCS v1 APIs as the v2 APIs were not fully developed enough on these builds to be usable.
This abstraction is done in HCSShim. (Referring specifically to runtime)

Note the LCOW graphdriver still uses HCS v1 APIs regardless.

Note also that this does not migrate docker to use containerd snapshotters
rather than graphdrivers. This needs to be done in conjunction with Linux also
doing the same switch.
2019-03-12 18:41:55 -07:00
Justin Cormack
98fc09128b Remove the rest of v1 manifest support
As people are using the UUID in `docker info` that was based on the v1 manifest signing key, replace
with a UUID instead.

Remove deprecated `--disable-legacy-registry` option that was scheduled to be removed in 18.03.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>
2019-03-02 10:46:37 -08:00
Ryo Nakao
894ecb24d1 Merge the divided loops
Signed-off-by: Ryo Nakao <nakabonne@gmail.com>
2019-02-24 16:16:19 +09:00
Akihiro Suda
ec87479b7e allow running dockerd in an unprivileged user namespace (rootless mode)
Please refer to `docs/rootless.md`.

TLDR:
 * Make sure `/etc/subuid` and `/etc/subgid` contain the entry for you
 * `dockerd-rootless.sh --experimental`
 * `docker -H unix://$XDG_RUNTIME_DIR/docker.sock run ...`

Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
2019-02-04 00:24:27 +09:00
Brian Goff
eaad3ee3cf Make sure timers are stopped after use.
`time.After` keeps a timer running until the specified duration is
completed. It also allocates a new timer on each call. This can wind up
leaving lots of uneccessary timers running in the background that are
not needed and consume resources.

Instead of `time.After`, use `time.NewTimer` so the timer can actually
be stopped.
In some of these cases it's not a big deal since the duraiton is really
short, but in others it is much worse.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2019-01-16 14:32:53 -08:00
Yong Tang
7315a2bb11 Fix go vet issue in daemon/daemon.go
This fix fixes go vet issue:
```
daemon/daemon.go:273: loop variable id captured by func literal
daemon/daemon.go:280: loop variable id captured by func literal
```

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
2019-01-06 00:18:29 +00:00
Akihiro Suda
2cb26cfe9c
Merge pull request #38301 from cyphar/waitgroup-limits
daemon: switch to semaphore-gated WaitGroup for startup tasks
2018-12-22 00:07:55 +09:00
Aleksa Sarai
5a52917e4d
daemon: switch to semaphore-gated WaitGroup for startup tasks
Many startup tasks have to run for each container, and thus using a
WaitGroup (which doesn't have a limit to the number of parallel tasks)
can result in Docker exceeding the NOFILE limit quite trivially. A more
optimal solution is to have a parallelism limit by using a semaphore.

In addition, several startup tasks were not parallelised previously
which resulted in very long startup times. According to my testing, 20K
dead containers resulted in ~6 minute startup times (during which time
Docker is completely unusable).

This patch fixes both issues, and the parallelStartupTimes factor chosen
(128 * NumCPU) is based on my own significant testing of the 20K
container case. This patch (on my machines) reduces the startup time
from 6 minutes to less than a minute (ideally this could be further
reduced by removing the need to scan all dead containers on startup --
but that's beyond the scope of this patchset).

In order to avoid the NOFILE limit problem, we also detect this
on-startup and if NOFILE < 2*128*NumCPU we will reduce the parallelism
factor to avoid hitting NOFILE limits (but also emit a warning since
this is almost certainly a mis-configuration).

Signed-off-by: Aleksa Sarai <asarai@suse.de>
2018-12-21 21:51:02 +11:00