On 26-Aug-19 2:44 PM, Jim Harris wrote:
Ideally, get_tsc_freq_arch() is able to provide the
TSC rate using arch-specific means. When that is not
possible, DPDK reverts to calculating the TSC rate with
a 100ms nanosleep or 1s sleep. The latter occurs more
frequently in VMs which often do not have access to the
data they need from arch-specific means (CPUID leaf 0x15
or MSR 0xCE on x86).
In secondary processes, the extra 100ms is especially
noticeable and consumes the bulk of rte_eal_init()
execution time. To resolve this extra delay, have
the primary process put the TSC rate into a shared
memory region that the secondary process can lookup.
Reduces rte_eal_init() execution time in a secondary
process from 165ms to 66ms on my test system.
Signed-off-by: Jim Harris <james.r.har...@intel.com>
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I think this is a bad idea. If you're allocating something, you're
supposed to free it in rte_eal_cleanup(). If you don't, that memory
leaks (i.e. there are leftover hugepages after process exit). Since both
primary and secondary are referencing it (even if only at init), there
is no safe way to free this memzone.
--
Thanks,
Anatoly
