1 #ifndef JEMALLOC_INTERNAL_SEC_OPTS_H 2 #define JEMALLOC_INTERNAL_SEC_OPTS_H 3 4 /* 5 * The configuration settings used by an sec_t. Morally, this is part of the 6 * SEC interface, but we put it here for header-ordering reasons. 7 */ 8 9 typedef struct sec_opts_s sec_opts_t; 10 struct sec_opts_s { 11 /* 12 * We don't necessarily always use all the shards; requests are 13 * distributed across shards [0, nshards - 1). 14 */ 15 size_t nshards; 16 /* 17 * We'll automatically refuse to cache any objects in this sec if 18 * they're larger than max_alloc bytes, instead forwarding such objects 19 * directly to the fallback. 20 */ 21 size_t max_alloc; 22 /* 23 * Exceeding this amount of cached extents in a shard causes us to start 24 * flushing bins in that shard until we fall below bytes_after_flush. 25 */ 26 size_t max_bytes; 27 /* 28 * The number of bytes (in all bins) we flush down to when we exceed 29 * bytes_cur. We want this to be less than bytes_cur, because 30 * otherwise we could get into situations where a shard undergoing 31 * net-deallocation keeps bytes_cur very near to max_bytes, so that 32 * most deallocations get immediately forwarded to the underlying PAI 33 * implementation, defeating the point of the SEC. 34 */ 35 size_t bytes_after_flush; 36 /* 37 * When we can't satisfy an allocation out of the SEC because there are 38 * no available ones cached, we allocate multiple of that size out of 39 * the fallback allocator. Eventually we might want to do something 40 * cleverer, but for now we just grab a fixed number. 41 */ 42 size_t batch_fill_extra; 43 }; 44 45 #define SEC_OPTS_DEFAULT { \ 46 /* nshards */ \ 47 4, \ 48 /* max_alloc */ \ 49 (32 * 1024) < PAGE ? PAGE : (32 * 1024), \ 50 /* max_bytes */ \ 51 256 * 1024, \ 52 /* bytes_after_flush */ \ 53 128 * 1024, \ 54 /* batch_fill_extra */ \ 55 0 \ 56 } 57 58 59 #endif /* JEMALLOC_INTERNAL_SEC_OPTS_H */ 60