Re: [PATCH v2] mem: balanced allocation of hugepages

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2017-04-10 11:04, Ilya Maximets:
> Currently EAL allocates hugepages one by one not paying
> attention from which NUMA node allocation was done.
> 
> Such behaviour leads to allocation failure if number of
> available hugepages for application limited by cgroups
> or hugetlbfs and memory requested not only from the first
> socket.
> 
> Example:
> 	# 90 x 1GB hugepages availavle in a system
> 
> 	cgcreate -g hugetlb:/test
> 	# Limit to 32GB of hugepages
> 	cgset -r hugetlb.1GB.limit_in_bytes=34359738368 test
> 	# Request 4GB from each of 2 sockets
> 	cgexec -g hugetlb:test testpmd --socket-mem=4096,4096 ...
> 
> 	EAL: SIGBUS: Cannot mmap more hugepages of size 1024 MB
> 	EAL: 32 not 90 hugepages of size 1024 MB allocated
> 	EAL: Not enough memory available on socket 1!
> 	     Requested: 4096MB, available: 0MB
> 	PANIC in rte_eal_init():
> 	Cannot init memory
> 
> 	This happens beacause all allocated pages are
> 	on socket 0.
> 
> Fix this issue by setting mempolicy MPOL_PREFERRED for each
> hugepage to one of requested nodes in a round-robin fashion.
> In this case all allocated pages will be fairly distributed
> between all requested nodes.
> 
> New config option RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES
> introduced and disabled by default because of external
> dependency from libnuma.
> 
> Fixes: 77988fc08dc5 ("mem: fix allocating all free hugepages")
> 
> Signed-off-by: Ilya Maximets <i.maximets@samsung.com>

Status: Changes Requested
per Sergio advice: "I would be inclined towards v3 targeting v17.08."