)]}'
{
  "log": [
    {
      "commit": "f5db4af466e2dca0fe822019812d586ca910b00c",
      "tree": "1bbaaa36509df9f7eecc19ccffa434048cf4b555",
      "parents": [
        "754c5fc7ebb417b23601a6222a6005cc2e7f2913"
      ],
      "author": {
        "name": "Jonthan Brassow",
        "email": "jbrassow@redhat.com",
        "time": "Mon Jun 22 10:12:35 2009 +0100"
      },
      "committer": {
        "name": "Alasdair G Kergon",
        "email": "agk@redhat.com",
        "time": "Mon Jun 22 10:12:35 2009 +0100"
      },
      "message": "dm raid1: add userspace log\n\nThis patch contains a device-mapper mirror log module that forwards\nrequests to userspace for processing.\n\nThe structures used for communication between kernel and userspace are\nlocated in include/linux/dm-log-userspace.h.  Due to the frequency,\ndiversity, and 2-way communication nature of the exchanges between\nkernel and userspace, \u0027connector\u0027 was chosen as the interface for\ncommunication.\n\nThe first log implementations written in userspace - \"clustered-disk\"\nand \"clustered-core\" - support clustered shared storage.   A userspace\ndaemon (in the LVM2 source code repository) uses openAIS/corosync to\nprocess requests in an ordered fashion with the rest of the nodes in the\ncluster so as to prevent log state corruption.  Other implementations\nwith no association to LVM or openAIS/corosync, are certainly possible.\n\n(Imagine if two machines are writing to the same region of a mirror.\nThey would both mark the region dirty, but you need a cluster-aware\nentity that can handle properly marking the region clean when they are\ndone.  Otherwise, you might clear the region when the first machine is\ndone, not the second.)\n\nSigned-off-by: Jonathan Brassow \u003cjbrassow@redhat.com\u003e\nCc: Evgeniy Polyakov \u003cjohnpol@2ka.mipt.ru\u003e\nSigned-off-by: Alasdair G Kergon \u003cagk@redhat.com\u003e\n"
    }
  ]
}
