Perhaps a cable connector that has partly come loose? Bad connections can cause
slow speeds, internal as well as external.
Cheers,
Tony
On 10 August 2017 7:46:04 AM AEST, Henry Poras <henry.poras@xxxxxxxxx> wrote:
I have two identical servers (or so I am told), but application work
is
running 2-3 times slower on one than the other. Using Tanel's snapper,
I
see that all active sessions are all on CPU. Viewing top shows me the
same
thing, each session pegs a cpu. We also found that it wasn't particular
SQL
that slowed down across severs, but it looked like everything was slow.
A
select count(*) from dba_objects showed this behavior as did Jonathan
Lewis's kill_cpu script. This gave me something to test with. Running a
10046, I saw the same amount of resource utilization (parse count,
fetch
count, cr count, ...), no contention (wait events), but one server
finished
2.5 times faster than the other. Looking at session stats through
snapper,
I see that the number of session logical reads per sec (~all of which
are
consistent reads) is ~ 2.5 times higher on one server than the other.
That
explains why it takes one longer to finish.
So, now what?? Why is one server giving me 350k consistent gets/per
second
and the other is ~800k? Is it hardware? /proc/cpuinfo shows the same
cpu
for each box. Is it hidden in the Oracle code path? I realize that not
all
LIO are created equal, but how do I check this? I am running on
SE12.1.0.1
Any and all thoughts welcome.
Henry
