after.perf

# Samples: 57  of event 'cpu-clock:uhpppH'
# Event count (approx.): 14250000
#
# Overhead  Command         Shared Object         Symbol                                                                                                                                                                                                
# ........  ..............  ....................  ......................................................................................................................................................................................................
#
     7.02%  (redacted)      ld-2.26.so            [.] do_lookup_x
     7.02%  (redacted)      libnss_files-2.26.so  [.] internal_getent
     5.26%  (redacted)      libresolv-2.26.so     [.] __res_context_send
     5.26%  (redacted)      (redacted)            [.] (redacted)
     3.51%  (redacted)      ld-2.26.so            [.] strcmp
     3.51%  (redacted)      libc-2.26.so          [.] __poll
     3.51%  (redacted)      (redacted)            [.] (redacted)
     3.51%  (redacted)      (redacted)            [.] (redacted)
     1.75%  (redacted)      ld-2.26.so            [.] _dl_relocate_object
     1.75%  (redacted)      libc-2.26.so          [.] __GI___fgets_unlocked
     1.75%  (redacted)      libc-2.26.so          [.] __libc_disable_asynccancel
     1.75%  (redacted)      libc-2.26.so          [.] __memmove_avx_unaligned_erms
     1.75%  (redacted)      libc-2.26.so          [.] __nss_next2
     1.75%  (redacted)      libc-2.26.so          [.] __snprintf
     1.75%  (redacted)      libc-2.26.so          [.] _res_hconf_reorder_addrs
     1.75%  (redacted)      libc-2.26.so          [.] getnameinfo
     1.75%  (redacted)      libc-2.26.so          [.] gni_host_inet_name.isra.1
     1.75%  (redacted)      libc-2.26.so          [.] nss_parse_service_list
     1.75%  (redacted)      libc-2.26.so          [.] resolv_conf_matches
     1.75%  (redacted)      libpthread-2.26.so    [.] __libc_recvfrom
     1.75%  (redacted)      libpthread-2.26.so    [.] __pthread_mutex_lock
     1.75%  (redacted)      libpthread-2.26.so    [.] __pthread_mutex_unlock
     1.75%  (redacted)      libresolv-2.26.so     [.] __res_context_query
     1.75%  (redacted)      libresolv-2.26.so     [.] ns_name_ntop
     1.75%  (redacted)      libresolv-2.26.so     [.] ns_name_pack
     1.75%  (redacted)      libresolv-2.26.so     [.] ns_name_unpack
     1.75%  (redacted)      libz.so.1.2.8         [.] register_tm_clones
     1.75%  (redacted)      (redacted)            [.] (redacted)
     1.75%  (redacted)      (redacted)            [.] (redacted)
     1.75%  (redacted)      (redacted)            [.] (redacted)
     1.75%  (redacted)      (redacted)            [.] (redacted)
<snip>

before.perf

# Samples: 1K of event 'cpu-clock:uhpppH'
# Event count (approx.): 285500000
#
# Overhead  Command         Shared Object         Symbol                                                                                                                                                                                                                                    
# ........  ..............  ....................  ..........................................................................................................................................................................................................................................
#
    36.08%  (redacted)      libnss_files-2.26.so  [.] _nss_files_parse_servent
    12.35%  (redacted)      libc-2.26.so          [.] __GI_____strtoull_l_internal
    11.56%  (redacted)      libnss_files-2.26.so  [.] internal_getent
     7.36%  (redacted)      libc-2.26.so          [.] __memchr_avx2
     5.25%  (redacted)      libc-2.26.so          [.] __memmove_avx_unaligned_erms
     4.90%  (redacted)      libc-2.26.so          [.] _IO_getline_info
     4.73%  (redacted)      libc-2.26.so          [.] __strpbrk_sse42
     2.98%  (redacted)      libc-2.26.so          [.] __strlen_avx2
     2.89%  (redacted)      libc-2.26.so          [.] __GI___fgets_unlocked
     1.75%  (redacted)      libc-2.26.so          [.] _IO_file_read
     1.05%  (redacted)      libnss_files-2.26.so  [.] _nss_files_getservbyport_r
     0.79%  (redacted)      libc-2.26.so          [.] __GI_strtoul
     0.61%  (redacted)      libnss_files-2.26.so  [.] __ctype_b_loc@plt
     0.53%  (redacted)      libc-2.26.so          [.] _IO_getline
     0.53%  (redacted)      libnss_files-2.26.so  [.] strtoul@plt
     0.53%  (redacted)      (redacted)            [.] (redacted)
     0.44%  (redacted)      libc-2.26.so          [.] __ctype_b_loc
     0.44%  (redacted)      (redacted)            [.] (redacted)
     0.26%  (redacted)      libc-2.26.so          [.] _IO_file_underflow@@GLIBC_2.2.5
     0.26%  (redacted)      libnss_files-2.26.so  [.] strpbrk@plt
     0.18%  (redacted)      ld-2.26.so            [.] do_lookup_x
     0.18%  (redacted)      libc-2.26.so          [.] _IO_default_uflow
     0.18%  (redacted)      libc-2.26.so          [.] fclose@@GLIBC_2.2.5
     0.18%  (redacted)      libnss_files-2.26.so  [.] internal_getent
     0.18%  (redacted)      libnss_files-2.26.so  [.] strlen@plt
     0.18%  (redacted)      libresolv-2.26.so     [.] ns_name_ntop
<snip>