)]}'
{"/COMMIT_MSG":[{"author":{"_account_id":11604,"name":"sean mooney","email":"smooney@redhat.com","username":"sean-k-mooney"},"change_message_id":"04cddd46f6c7dd4420abd225f385a3a9529ee4c1","unresolved":true,"context_lines":[{"line_number":4,"context_line":"Commit:     Bogdan Dobrelya \u003cbdobreli@redhat.com\u003e"},{"line_number":5,"context_line":"CommitDate: 2021-05-21 10:07:52 +0200"},{"line_number":6,"context_line":""},{"line_number":7,"context_line":"Use writethrough since writeback is not safe"},{"line_number":8,"context_line":""},{"line_number":9,"context_line":"Writeback disk caching should never be used since it"},{"line_number":10,"context_line":"leads to corrupted data. Allow this setting to come from hiera"},{"line_number":11,"context_line":"overrides as well."},{"line_number":12,"context_line":""},{"line_number":13,"context_line":"Change-Id: I47aaf4be463684f5b67820b8ebb5db44ba960b44"}],"source_content_type":"text/x-gerrit-commit-message","patch_set":4,"id":"15924ce3_debdc46b","line":10,"range":{"start_line":7,"start_character":0,"end_line":10,"end_character":23},"updated":"2021-05-21 09:00:27.000000000","message":"im not sure this statement is true.\n\nits in direct contodciton to the logic we have applied in nova\nfor chosing between writeback, none and writetrough\nhttps://opendev.org/openstack/nova/commit/b9dc86d8d6\n\nkasyap has look at the detail of how the cache mdoes work several times\ni think he should review this change.","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"},{"author":{"_account_id":6962,"name":"Kashyap Chamarthy","email":"kchamart@redhat.com","username":"kashyapc"},"change_message_id":"d021a1fc5c944e7a2f2f416ce6562c72c4f407b2","unresolved":true,"context_lines":[{"line_number":4,"context_line":"Commit:     Bogdan Dobrelya \u003cbdobreli@redhat.com\u003e"},{"line_number":5,"context_line":"CommitDate: 2021-05-21 10:07:52 +0200"},{"line_number":6,"context_line":""},{"line_number":7,"context_line":"Use writethrough since writeback is not safe"},{"line_number":8,"context_line":""},{"line_number":9,"context_line":"Writeback disk caching should never be used since it"},{"line_number":10,"context_line":"leads to corrupted data. Allow this setting to come from hiera"},{"line_number":11,"context_line":"overrides as well."},{"line_number":12,"context_line":""},{"line_number":13,"context_line":"Change-Id: I47aaf4be463684f5b67820b8ebb5db44ba960b44"}],"source_content_type":"text/x-gerrit-commit-message","patch_set":4,"id":"b9654cbd_61146bc3","line":10,"range":{"start_line":7,"start_character":0,"end_line":10,"end_character":23},"in_reply_to":"15924ce3_debdc46b","updated":"2021-05-21 09:21:08.000000000","message":"Hi,\n\n\"Writeback should never be used\" is completely incorrect.\n\n- \"writethrough\" is slow and is _not_ recommended by QEMU Block Layer maintainers in general, as the \"write\" performance is slow with it.\n\n- when \"none\" is not available; then \"writeback\" is the most-recommended.  (Please see the documentation here: https://opendev.org/openstack/nova/commit/b9dc86d8d6)\n\n- Ceph upstream recommends \"writeback\" when you\u0027re using \"rbd_cache\u003dtrue\" to avoid data loss:\n\n  [quote]\n  If you set rbd_cache\u003dtrue, you must set cache\u003dwriteback or risk \n  data loss. Without cache\u003dwriteback, QEMU will not send flush \n  requests to librbd. If QEMU exits uncleanly in this \n  configuration, file systems on top of rbd can be corrupted.\n  [/quote]\n\nWe also note this in Nova\u0027s cache modes documentation (see nova/conf/libvirt.py)\n\n[1] https://docs.ceph.com/en/latest/rbd/qemu-rbd/","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"},{"author":{"_account_id":6926,"name":"Bogdan Dobrelya","email":"bdobreli@redhat.com","username":"bogdando"},"change_message_id":"64f655510296b6b149c75f49ae39ddba8fe13455","unresolved":false,"context_lines":[{"line_number":4,"context_line":"Commit:     Bogdan Dobrelya \u003cbdobreli@redhat.com\u003e"},{"line_number":5,"context_line":"CommitDate: 2021-05-21 10:07:52 +0200"},{"line_number":6,"context_line":""},{"line_number":7,"context_line":"Use writethrough since writeback is not safe"},{"line_number":8,"context_line":""},{"line_number":9,"context_line":"Writeback disk caching should never be used since it"},{"line_number":10,"context_line":"leads to corrupted data. Allow this setting to come from hiera"},{"line_number":11,"context_line":"overrides as well."},{"line_number":12,"context_line":""},{"line_number":13,"context_line":"Change-Id: I47aaf4be463684f5b67820b8ebb5db44ba960b44"}],"source_content_type":"text/x-gerrit-commit-message","patch_set":4,"id":"e4ba8c8c_ed86b5ee","line":10,"range":{"start_line":7,"start_character":0,"end_line":10,"end_character":23},"in_reply_to":"3fc524ac_52dbfef1","updated":"2021-05-21 13:30:48.000000000","message":"Done","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"},{"author":{"_account_id":6926,"name":"Bogdan Dobrelya","email":"bdobreli@redhat.com","username":"bogdando"},"change_message_id":"847c977509351a78f9b043940d51f1a4ba0d7b8c","unresolved":true,"context_lines":[{"line_number":4,"context_line":"Commit:     Bogdan Dobrelya \u003cbdobreli@redhat.com\u003e"},{"line_number":5,"context_line":"CommitDate: 2021-05-21 10:07:52 +0200"},{"line_number":6,"context_line":""},{"line_number":7,"context_line":"Use writethrough since writeback is not safe"},{"line_number":8,"context_line":""},{"line_number":9,"context_line":"Writeback disk caching should never be used since it"},{"line_number":10,"context_line":"leads to corrupted data. Allow this setting to come from hiera"},{"line_number":11,"context_line":"overrides as well."},{"line_number":12,"context_line":""},{"line_number":13,"context_line":"Change-Id: I47aaf4be463684f5b67820b8ebb5db44ba960b44"}],"source_content_type":"text/x-gerrit-commit-message","patch_set":4,"id":"3fc524ac_52dbfef1","line":10,"range":{"start_line":7,"start_character":0,"end_line":10,"end_character":23},"in_reply_to":"6073c75e_b043d4ba","updated":"2021-05-21 13:02:48.000000000","message":"thank you, that\u0027s a lot of feedback!\nI\u0027ll keep the default then","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"},{"author":{"_account_id":10135,"name":"Lee Yarwood","display_name":"Lee Yarwood","email":"lyarwood@redhat.com","username":"lyarwood"},"change_message_id":"a9da858cdbd40c5bc3960f987336a3973491b69a","unresolved":true,"context_lines":[{"line_number":4,"context_line":"Commit:     Bogdan Dobrelya \u003cbdobreli@redhat.com\u003e"},{"line_number":5,"context_line":"CommitDate: 2021-05-21 10:07:52 +0200"},{"line_number":6,"context_line":""},{"line_number":7,"context_line":"Use writethrough since writeback is not safe"},{"line_number":8,"context_line":""},{"line_number":9,"context_line":"Writeback disk caching should never be used since it"},{"line_number":10,"context_line":"leads to corrupted data. Allow this setting to come from hiera"},{"line_number":11,"context_line":"overrides as well."},{"line_number":12,"context_line":""},{"line_number":13,"context_line":"Change-Id: I47aaf4be463684f5b67820b8ebb5db44ba960b44"}],"source_content_type":"text/x-gerrit-commit-message","patch_set":4,"id":"6073c75e_b043d4ba","line":10,"range":{"start_line":7,"start_character":0,"end_line":10,"end_character":23},"in_reply_to":"b9654cbd_61146bc3","updated":"2021-05-21 09:35:16.000000000","message":"\u003e Hi,\n\u003e \n\u003e \"Writeback should never be used\" is completely incorrect.\n\u003e \n\u003e - \"writethrough\" is slow and is _not_ recommended by QEMU Block Layer maintainers in general, as the \"write\" performance is slow with it.\n\nI\u0027ve recommended writethrough downstream in the InstanceHA usecase where the host compute can be power fenced to ensure data isn\u0027t cached. That\u0027s pretty much the only use case I can think of where writethrough or directsync would be useful with rbd, otherwise I agree that the default should remain as writeback.\n\n\u003e - when \"none\" is not available; then \"writeback\" is the most-recommended.  (Please see the documentation here: https://opendev.org/openstack/nova/commit/b9dc86d8d6)\n\u003e \n\u003e - Ceph upstream recommends \"writeback\" when you\u0027re using \"rbd_cache\u003dtrue\" to avoid data loss:\n\u003e \n\u003e   [quote]\n\u003e   If you set rbd_cache\u003dtrue, you must set cache\u003dwriteback or risk \n\u003e   data loss. Without cache\u003dwriteback, QEMU will not send flush \n\u003e   requests to librbd. If QEMU exits uncleanly in this \n\u003e   configuration, file systems on top of rbd can be corrupted.\n\u003e   [/quote]\n\nIt\u0027s worth highlighting that rbd_cache\u003dtrue here refers to an old QEMU command line -drive argument and this overrides anything set in ceph.conf:\n\nhttps://docs.ceph.com/en/latest/rbd/qemu-rbd/#qemu-cache-options\n\n\u003e QEMU’s cache settings override Ceph’s cache settings (including \n\u003e settings that are explicitly set in the Ceph configuration file).","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"}],"manifests/profile/base/nova/compute_libvirt_shared.pp":[{"author":{"_account_id":6796,"name":"Giulio Fidente","email":"gfidente@redhat.com","username":"gfidente"},"change_message_id":"cfc11268a5fc380cd8dc843c0f57ff447b0c9271","unresolved":true,"context_lines":[{"line_number":56,"context_line":""},{"line_number":57,"context_line":"    if $rbd_ephemeral_storage {"},{"line_number":58,"context_line":"      class { \u0027nova::compute::libvirt\u0027:"},{"line_number":59,"context_line":"        disk_cachemodes \u003d\u003e [\u0027network\u003dwritethrough\u0027],"},{"line_number":60,"context_line":"        hw_disk_discard \u003d\u003e \u0027unmap\u0027,"},{"line_number":61,"context_line":"      }"},{"line_number":62,"context_line":"    } else {"}],"source_content_type":"text/x-puppet","patch_set":1,"id":"d228b44d_efe0e267","line":59,"updated":"2021-05-20 22:17:56.000000000","message":"maybe it\u0027s a good chance to turn this into an actual parameter?","commit_id":"8f3a6c2b4a3353216b5555773a0a11d78b802ee3"},{"author":{"_account_id":17216,"name":"Martin Schuppert","email":"mschuppert@redhat.com","username":"mcschupp"},"change_message_id":"62ca64d718a187a89670120c5575d6c9aa445bbf","unresolved":true,"context_lines":[{"line_number":56,"context_line":""},{"line_number":57,"context_line":"    if $rbd_ephemeral_storage {"},{"line_number":58,"context_line":"      class { \u0027nova::compute::libvirt\u0027:"},{"line_number":59,"context_line":"        disk_cachemodes \u003d\u003e [\u0027network\u003dwritethrough\u0027],"},{"line_number":60,"context_line":"        hw_disk_discard \u003d\u003e \u0027unmap\u0027,"},{"line_number":61,"context_line":"      }"},{"line_number":62,"context_line":"    } else {"}],"source_content_type":"text/x-puppet","patch_set":1,"id":"1635397c_bbcc18b3","line":59,"in_reply_to":"99aa3fbc_e751b415","updated":"2021-05-21 06:09:14.000000000","message":"I mean using a parameter 😊","commit_id":"8f3a6c2b4a3353216b5555773a0a11d78b802ee3"},{"author":{"_account_id":17216,"name":"Martin Schuppert","email":"mschuppert@redhat.com","username":"mcschupp"},"change_message_id":"a3b3569c6a8fece118efa1b27bba28389290a3bb","unresolved":true,"context_lines":[{"line_number":56,"context_line":""},{"line_number":57,"context_line":"    if $rbd_ephemeral_storage {"},{"line_number":58,"context_line":"      class { \u0027nova::compute::libvirt\u0027:"},{"line_number":59,"context_line":"        disk_cachemodes \u003d\u003e [\u0027network\u003dwritethrough\u0027],"},{"line_number":60,"context_line":"        hw_disk_discard \u003d\u003e \u0027unmap\u0027,"},{"line_number":61,"context_line":"      }"},{"line_number":62,"context_line":"    } else {"}],"source_content_type":"text/x-puppet","patch_set":1,"id":"99aa3fbc_e751b415","line":59,"in_reply_to":"d228b44d_efe0e267","updated":"2021-05-21 06:08:20.000000000","message":"yes I agree, we probably should not change the default without to option change it","commit_id":"8f3a6c2b4a3353216b5555773a0a11d78b802ee3"},{"author":{"_account_id":6926,"name":"Bogdan Dobrelya","email":"bdobreli@redhat.com","username":"bogdando"},"change_message_id":"2368b615548e0cf2dfa532933763cec43ee62f00","unresolved":true,"context_lines":[{"line_number":40,"context_line":"    # Ceph + Libvirt"},{"line_number":41,"context_line":"    $rbd_ephemeral_storage  \u003d hiera(\u0027nova::compute::rbd::ephemeral_storage\u0027, false)"},{"line_number":42,"context_line":"    $rbd_persistent_storage \u003d hiera(\u0027rbd_persistent_storage\u0027, false)"},{"line_number":43,"context_line":"    $rbd_disk_cachemodes    \u003d hiera(\u0027rbd_disk_cachemodes\u0027, [\u0027network \u003d writethrough\u0027])"},{"line_number":44,"context_line":"    if $rbd_ephemeral_storage or $rbd_persistent_storage {"},{"line_number":45,"context_line":"      include nova::compute::rbd"},{"line_number":46,"context_line":"      exec{ \"exec-setfacl-${nova_rbd_client_name}-nova\":"}],"source_content_type":"text/x-puppet","patch_set":3,"id":"ad16f5e1_6c57383b","line":43,"updated":"2021-05-21 07:51:22.000000000","message":"do we want it differentiated for Cinder vs Nova?","commit_id":"051b3920cb5917f1d5bcd594196b06d75632168e"},{"author":{"_account_id":11604,"name":"sean mooney","email":"smooney@redhat.com","username":"sean-k-mooney"},"change_message_id":"04cddd46f6c7dd4420abd225f385a3a9529ee4c1","unresolved":true,"context_lines":[{"line_number":40,"context_line":"    # Ceph + Libvirt"},{"line_number":41,"context_line":"    $rbd_ephemeral_storage  \u003d hiera(\u0027nova::compute::rbd::ephemeral_storage\u0027, false)"},{"line_number":42,"context_line":"    $rbd_persistent_storage \u003d hiera(\u0027rbd_persistent_storage\u0027, false)"},{"line_number":43,"context_line":"    $rbd_disk_cachemodes    \u003d hiera(\u0027rbd_disk_cachemodes\u0027, [\u0027network\u003dwritethrough\u0027])"},{"line_number":44,"context_line":"    if $rbd_ephemeral_storage or $rbd_persistent_storage {"},{"line_number":45,"context_line":"      include nova::compute::rbd"},{"line_number":46,"context_line":"      exec{ \"exec-setfacl-${nova_rbd_client_name}-nova\":"}],"source_content_type":"text/x-puppet","patch_set":4,"id":"9c5b1345_163f7849","line":43,"range":{"start_line":43,"start_character":4,"end_line":43,"end_character":84},"updated":"2021-05-21 09:00:27.000000000","message":"this still changes the default so you have not adressed martins previous -1\nthis should still be writeback","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"},{"author":{"_account_id":6926,"name":"Bogdan Dobrelya","email":"bdobreli@redhat.com","username":"bogdando"},"change_message_id":"57ad16b4ad88898aebd75662af2e1cb99d8e42c4","unresolved":true,"context_lines":[{"line_number":40,"context_line":"    # Ceph + Libvirt"},{"line_number":41,"context_line":"    $rbd_ephemeral_storage  \u003d hiera(\u0027nova::compute::rbd::ephemeral_storage\u0027, false)"},{"line_number":42,"context_line":"    $rbd_persistent_storage \u003d hiera(\u0027rbd_persistent_storage\u0027, false)"},{"line_number":43,"context_line":"    $rbd_disk_cachemodes    \u003d hiera(\u0027rbd_disk_cachemodes\u0027, [\u0027network\u003dwritethrough\u0027])"},{"line_number":44,"context_line":"    if $rbd_ephemeral_storage or $rbd_persistent_storage {"},{"line_number":45,"context_line":"      include nova::compute::rbd"},{"line_number":46,"context_line":"      exec{ \"exec-setfacl-${nova_rbd_client_name}-nova\":"}],"source_content_type":"text/x-puppet","patch_set":4,"id":"f27100db_80e94dfd","line":43,"range":{"start_line":43,"start_character":4,"end_line":43,"end_character":84},"in_reply_to":"9c5b1345_163f7849","updated":"2021-05-21 13:03:40.000000000","message":"yeah, I\u0027ve overlooked that previous comment, sorry","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"},{"author":{"_account_id":6926,"name":"Bogdan Dobrelya","email":"bdobreli@redhat.com","username":"bogdando"},"change_message_id":"64f655510296b6b149c75f49ae39ddba8fe13455","unresolved":false,"context_lines":[{"line_number":40,"context_line":"    # Ceph + Libvirt"},{"line_number":41,"context_line":"    $rbd_ephemeral_storage  \u003d hiera(\u0027nova::compute::rbd::ephemeral_storage\u0027, false)"},{"line_number":42,"context_line":"    $rbd_persistent_storage \u003d hiera(\u0027rbd_persistent_storage\u0027, false)"},{"line_number":43,"context_line":"    $rbd_disk_cachemodes    \u003d hiera(\u0027rbd_disk_cachemodes\u0027, [\u0027network\u003dwritethrough\u0027])"},{"line_number":44,"context_line":"    if $rbd_ephemeral_storage or $rbd_persistent_storage {"},{"line_number":45,"context_line":"      include nova::compute::rbd"},{"line_number":46,"context_line":"      exec{ \"exec-setfacl-${nova_rbd_client_name}-nova\":"}],"source_content_type":"text/x-puppet","patch_set":4,"id":"111ff214_bd0d24f1","line":43,"range":{"start_line":43,"start_character":4,"end_line":43,"end_character":84},"in_reply_to":"f27100db_80e94dfd","updated":"2021-05-21 13:30:48.000000000","message":"Done","commit_id":"dce208b190b4c820d63074389b1c4f4073977674"}]}