mesos git commit: Added a warning comment to the copy provisioner backend.

[ya...@apache.org]

Repository: mesos
Updated Branches:
  refs/heads/master 2876b8c91 -> cfecd7fd7


Added a warning comment to the copy provisioner backend.

- We should investigate how to resolve these implications or disable/discourage the use of this backend in production after the overlay backend is committed.

Review: https://reviews.apache.org/r/38511


Project: http://git-wip-us.apache.org/repos/asf/mesos/repo
Commit: http://git-wip-us.apache.org/repos/asf/mesos/commit/cfecd7fd
Tree: http://git-wip-us.apache.org/repos/asf/mesos/tree/cfecd7fd
Diff: http://git-wip-us.apache.org/repos/asf/mesos/diff/cfecd7fd

Branch: refs/heads/master
Commit: cfecd7fd70f9952024915c476003de06d31c91f4
Parents: 2876b8c
Author: Jiang Yan Xu <ya...@jxu.me>
Authored: Fri Sep 18 15:11:09 2015 -0700
Committer: Jiang Yan Xu <ya...@jxu.me>
Committed: Mon Sep 21 11:29:59 2015 -0700

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 src/slave/containerizer/provisioner/backends/copy.hpp | 8 ++++++++
 1 file changed, 8 insertions(+)
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http://git-wip-us.apache.org/repos/asf/mesos/blob/cfecd7fd/src/slave/containerizer/provisioner/backends/copy.hpp
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diff --git a/src/slave/containerizer/provisioner/backends/copy.hpp b/src/slave/containerizer/provisioner/backends/copy.hpp
index 10d9aee..7a5aaa4 100644
--- a/src/slave/containerizer/provisioner/backends/copy.hpp
+++ b/src/slave/containerizer/provisioner/backends/copy.hpp
@@ -29,6 +29,14 @@ namespace slave {
 class CopyBackendProcess;
 
 
+// The backend implementation that copies the layers to the target.
+// NOTE: Using this backend currently has a few implications:
+// 1) The disk space used by the provisioned rootfs is not counted
+//    towards either the usage by the executor/task or the store
+//    cache, which can interfere with the slave hosts's disk space
+//    allocation.
+// 2) The task can write unrestrictedly into the provisioned rootfs
+//    which is not accounted for (in terms of disk usage) either.
 class CopyBackend : public Backend
 {
 public: