Hi, I've run into bihash crashing VPP with an out-of-memory error. After investigation I found that the bihash has reached its configured memory limit with far less entries that I would have expected. Some numbers:
Type: bihash_8_8 bihash max. memory: 64MB Buckets: 1024 Entries 200k With that number it turns out that almost all buckets have 2^9 pages (512 pages). On average 200 entries per bucket are actually used. The total memory consumption from the buckets and pages should be 1024 * sizeof(bucket) + 1024 * 2^9 * sizeof(page) = 33 MB Yet the bihash has consumed all 64MB (alloc_arena_next > memory_size). It turned out that the missing memory was in the freelists for smaller page sizes. I have resized the bihash to have more buckets to avoid the large pages. Is there anything else I can do? I was thinking about enhancing bihash to specify a initial page size. This would waste some memory while the hash is growing, but would later avoid the fragmentation. Does that make sense? Regards Andreas -- Andreas Schultz -- Principal Engineer t: +49 391 819099-224 ------------------------------- enabling your networks ----------------------------- Travelping GmbH Roentgenstraße 13 39108 Magdeburg Germany t: +49 391 819099-0 f: +49 391 819099-299 e: [email protected] w: https://www.travelping.com/ Company registration: Amtsgericht Stendal Reg. No.: HRB 10578 Geschaeftsfuehrer: Holger Winkelmann VAT ID: DE236673780
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