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Date:      Wed, 4 Oct 1995 06:57:52 +1000
From:      Bruce Evans <bde@zeta.org.au>
To:        current@freebsd.org
Subject:   lmbench 1.1.5 vs 2.2-current
Message-ID:  <199510032057.GAA30471@godzilla.zeta.org.au>

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2.2-current seems to be significantly slower than 1.1.5 in many areas.

These benchmarks were run on the same machine except for a faster disk
and a possibly different L2 cache setting for 2.2-current.

The faster disk and clustering speed up the file reread benchmark by a
factor of 8.  The local tcp bandwidth is anomalously slow in
2.2-current.  mmap has been tuned for faster access at a cost of
increased setup overhead in 2.2-current.  Otherwise, these benchmarks
show unexplained lossages (probably mostly due to vfs bloat) of 10-40%
for 2.2-current.

lmbench only runs properly on systems with significantly more than
16MB of memory because it does one test that wants 2 8MB arrays in
memory at the same time.  I usually delete one 8192 to eliminate the
bogus test.  More things break on 8MB machines.  Has anyone fixed
this properly? (the current port doesn't).

Bruce

                    L M B E N C H  1 . 0   S U M M A R Y
                    ------------------------------------

            Processor, Processes - times in microseconds
            --------------------------------------------
Host                 OS  Mhz    Null    Null  Simple /bin/sh Mmap 2-proc 8-proc
                             Syscall Process Process Process  lat  ctxsw  ctxsw
--------- ------------- ---- ------- ------- ------- ------- ---- ------ ------
Alphplex. FreeBSD 1.1.5   66      19    8.2K   35.4K     88K 2299     33     40
alphplex  FreeBSD 2.2-C   66      30    6.8K   32.5K     91K  313     56     59

            *Local* Communication latencies in microseconds
            -----------------------------------------------
Host                 OS  Pipe       UDP    RPC/     TCP    RPC/
                                            UDP             TCP
--------- ------------- ------- ------- ------- ------- -------
Alphplex. FreeBSD 1.1.5     210     505     953     731    1320
alphplex  FreeBSD 2.2-C     285     626    1249     743    1452

            *Local* Communication bandwidths in megabytes/second
            ----------------------------------------------------
Host                 OS Pipe  TCP  File   Mmap  Bcopy  Bcopy  Mem   Mem
                                  reread reread (libc) (hand) read write
--------- ------------- ---- ---- ------ ------ ------ ------ ---- -----
Alphplex. FreeBSD 1.1.5    8  4.3    1.1    5.3     17      0    0    30
alphplex  FreeBSD 2.2-C    8  0.2    8.6   12.4     17      0    0    30

	    Memory latencies in nanoseconds
            (WARNING - may not be correct, check graphs)
            --------------------------------------------
Host                 OS   Mhz  L1 $   L2 $    Main mem    TLB    Guesses
--------- -------------   ---  ----   ----    --------    ---    -------
Alphplex. FreeBSD 1.1.5    66    18    295         731    971
alphplex  FreeBSD 2.2-C    66    18    379         733    909

                L M B E N C H  1 . 0   S U M M A R Y
                ------------------------------------

                  Comparison to best of the breed
                  -------------------------------

		(Best numbers are starred, i.e., *123)


        Processor, Processes - factor slower than the best
        --------------------------------------------------
Host                 OS  Mhz    Null    Null  Simple /bin/sh Mmap 2-proc 8-proc
                             Syscall Process Process Process  lat  ctxsw  ctxsw
--------- ------------- ---- ------- ------- ------- ------- ---- ------ ------
Alphplex. FreeBSD 1.1.5   66     *19     1.2     1.1  *85.6K  7.3    *33    *40
alphplex  FreeBSD 2.2-C   66     1.6   *6.7K  *31.7K     1.0 *313    1.7    1.5

        *Local* Communication latencies - factor slower than the best
        -------------------------------------------------------------
Host                 OS  Pipe       UDP    RPC/     TCP    RPC/
                                            UDP             TCP
--------- ------------- ------- ------- ------- ------- -------
Alphplex. FreeBSD 1.1.5    *210    *505    *953    *731   *1320
alphplex  FreeBSD 2.2-C     1.4     1.2     1.3     1.0     1.1

        *Local* Communication bandwidths - percentage of the best
        ---------------------------------------------------------
Host                 OS Pipe  TCP  File   Mmap  Bcopy  Bcopy  Mem   Mem
                                  reread reread (libc) (hand) read write
--------- ------------- ---- ---- ------ ------ ------ ------ ---- -----
Alphplex. FreeBSD 1.1.5   *8   *4    13%    42%    99%     *0   *0   99%
alphplex  FreeBSD 2.2-C   *8   4%     *8    *12    *16     *0   *0   *30

            Memory latencies in nanoseconds - factor slower than the best
		    (WARNING - may not be correct, check graphs)
            -------------------------------------------------------------
Host                 OS   Mhz  L1 $   L2 $    Main mem    TLB    Guesses
--------- -------------   ---  ----   ----    --------    ---    -------
Alphplex. FreeBSD 1.1.5    66   *18   *295        *731    1.1
alphplex  FreeBSD 2.2-C    66   *18    1.3         1.0   *909



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