Ubuntu
zfs-linux package

  1. Bug #1567557
  2. Comment #6

Comment 6 for bug 1567557

Revision history for this message
Colin Ian King (colin-king) wrote : Re: Performance degradation of "zfs clone" when under load

Most of the CPU being consumed is in strcmp()

- 99.39% 0.00% zfs [kernel.kallsyms] [k] zfsdev_ioctl ▒
   - 99.39% zfsdev_ioctl
      - 99.34% zfs_ioc_objset_stats
         - 99.22% zfs_ioc_objset_stats_impl.part.20
            - 99.01% dmu_objset_stats
               - 99.00% dsl_dataset_stats
                  - 98.98% get_clones_stat
                     - 62.55% fnvlist_add_nvlist
                          nvlist_add_nvlist
                          nvlist_add_common.part.51
                          nvlist_copy_embedded.isra.54
                        - nvlist_copy_pairs.isra.52
                           - 62.52% nvlist_add_common.part.51
                              - 31.25% nvlist_copy_embedded.isra.54
                                 - nvlist_copy_pairs.isra.52
                                    - 31.23% nvlist_add_common.part.51
                                       - 30.78% nvlist_remove_all.part.49
                                            strcmp
                              - 30.86% nvlist_remove_all.part.49
                                   strcmp
                     - 31.73% fnvlist_add_boolean
                        - nvlist_add_boolean
                           - 31.72% nvlist_add_common.part.51
                              - 31.33% nvlist_remove_all.part.49
                                   strcmp
                     + 4.16% dsl_dataset_hold_obj