Subject: Re: [PATCH] slub: Don't throw away partial remote slabs if there is no local memory

From: Andi Kleen <[email-masked]>
Date: Mon, 06 Jan 2014 22:49:53 -0800

Anton Blanchard <[email-masked]> writes:
>
> Thoughts? It seems like we could hit a similar situation if a machine
> is balanced but we run out of memory on a single node.

Yes I agree, but your patch doesn't seem to attempt to handle this?

-Andi
>
> Index: b/mm/slub.c
> ===================================================================
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -2278,10 +2278,17 @@ redo:
>  
>  	if (unlikely(!node_match(page, node))) {
>  		stat(s, ALLOC_NODE_MISMATCH);
> -		deactivate_slab(s, page, c->freelist);
> -		c->page = NULL;
> -		c->freelist = NULL;
> -		goto new_slab;
> +
> +		/*
> +		 * If the node contains no memory there is no point in trying
> +		 * to allocate a new node local slab
> +		 */
> +		if (node_spanned_pages(node)) {
> +			deactivate_slab(s, page, c->freelist);
> +			c->page = NULL;
> +			c->freelist = NULL;
> +			goto new_slab;
> +		}
>  	}
>  
>  	/*
-- 
[email-masked] -- Speaking for myself only