b13d3cbfb8
When the high_thresh limit is reached we try to toss the 'oldest' incomplete fragment queues until memory limits are below the low_thresh value. This happens in softirq/packet processing context. This has two drawbacks: 1) processors might evict a queue that was about to be completed by another cpu, because they will compete wrt. resource usage and resource reclaim. 2) LRU list maintenance is expensive. But when constantly overloaded, even the 'least recently used' element is recent, so removing 'lru' queue first is not 'fairer' than removing any other fragment queue. This moves eviction out of the fast path: When the low threshold is reached, a work queue is scheduled which then iterates over the table and removes the queues that exceed the memory limits of the namespace. It sets a new flag called INET_FRAG_EVICTED on the evicted queues so the proper counters will get incremented when the queue is forcefully expired. When the high threshold is reached, no more fragment queues are created until we're below the limit again. The LRU list is now unused and will be removed in a followup patch. Joint work with Nikolay Aleksandrov. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| dt-bindings | ||
| keys | ||
| kvm | ||
| linux | ||
| math-emu | ||
| media | ||
| memory | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| video | ||
| xen | ||
| Kbuild | ||