Radix vs etcd strace

01-radix.txt

Collected on an m5.large w/EBS over 360 seconds, with Yourkit attached.
Processing ~12 txns/sec. Roughly 135 fdatasync/sec.

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ------------------
 82.87 4517.437388        1806   2501189    265686 futex
 10.14  552.731643         827    668347           epoll_wait
  2.79  152.224778        6695     22737           clock_nanosleep
  1.59   86.877871     1357466        64           poll
  1.54   84.028244     3112157        27        16 restart_syscall
  0.28   15.203712         311     48776           fdatasync
  0.21   11.449301          10   1123963        10 read
  0.14    7.564838           8    940720           clock_gettime
  0.12    6.526628          15    411377           writev
  0.11    5.978851           9    615864           epoll_ctl
  0.10    5.220236          12    415630           write
  0.07    3.813035           8    456599           lseek
  0.02    0.839963          15     55748           fstat
  0.01    0.528579          11     46590           gettid
  0.00    0.148788        2289        65           unlink
  0.00    0.143524          19      7409           pread64
  0.00    0.068923          16      4207       105 openat
  0.00    0.065539          10      5965           getrusage
  0.00    0.046033          11      4098           close
  0.00    0.037863          11      3319           rt_sigprocmask
  0.00    0.030405          33       916           mmap
  0.00    0.019732          13      1481       123 stat
  0.00    0.017375          18       935           sched_getaffinity
  0.00    0.015469          33       463           madvise
  0.00    0.014869          13      1108           sendmsg
  0.00    0.014522          32       450           clone
  0.00    0.014493          16       864       432 recvmsg
  0.00    0.010567          23       450           mprotect
  0.00    0.006740          14       450           prctl
  0.00    0.006556          14       460           sysinfo
  0.00    0.006350          14       450           set_robust_list
  0.00    0.005987           5      1087         4 rt_sigreturn
  0.00    0.004713          12       365           statfs
  0.00    0.002862          40        70           fcntl
  0.00    0.000668          19        35           access
  0.00    0.000232           3        62           sched_yield
------ ----------- ----------- --------- --------- ------------------
100.00 5451.107277         742   7342340    266376 total

02-etcd.txt

Same cluster, this time with etcd pushing 2700 writes/sec. This sample
taken over ~120 seconds. ~750 calls to fdatasync per second, but
only .27 fsyncs per txn.

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 60.64  160.668617         243    659266     17575 futex
 14.78   39.162109          44    877282           select
 11.65   30.875094         344     89697           fdatasync
  6.98   18.482369          40    459453           epoll_wait
  1.69    4.488873          11    397278    140569 read
  1.58    4.195949          17    246290           write
  0.78    2.056633           9    220320           setsockopt
  0.43    1.147139          13     85634     30553 accept4
  0.42    1.121186          10    110162           epoll_ctl
  0.41    1.078441          10     98658           lseek
  0.36    0.942449          17     55185           close
  0.20    0.518954           9     55081           getsockname
  0.06    0.147927          11     13271           sched_yield
  0.01    0.032694         908        36           fsync
  0.00    0.012611           9      1312         8 lstat
  0.00    0.006640        3320         2         1 restart_syscall
  0.00    0.001814          54        33           unlinkat
  0.00    0.001592          15       104           openat
  0.00    0.001392          21        66           getdents64
  0.00    0.001345          13       102           pwrite64
  0.00    0.000440          11        37           fcntl
  0.00    0.000297          11        25           getrlimit
  0.00    0.000112          56         2           ftruncate
  0.00    0.000066          33         2           fallocate
  0.00    0.000064          21         3           rt_sigprocmask
  0.00    0.000045          45         1           clone
  0.00    0.000026          13         2           renameat
  0.00    0.000008           4         2           sigaltstack
  0.00    0.000008           4         2           gettid
  0.00    0.000006           6         1           arch_prctl
  0.00    0.000000           0         1           mmap
------ ----------- ----------- --------- --------- ----------------
100.00  264.944900          78   3369310    188706 total