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Type:
Task
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Resolution: Duplicate
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Priority:
Minor - P4
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None
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Affects Version/s: None
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Component/s: None
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Labels:None
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Fully Compatible
This is the cache section from db.serverStatus() after running a busy workload for about a few minutes. Note that mongod was started immediately prior to the test.
How can this possibly be true after a few minutes?
"pages evicted by application threads" : 3938125731,
I thought that maybe it counted bytes, which is possible given:
"bytes written from cache" : 4421343996,
But from looking at the code it just counts the number of calls to __wt_evict_lru_page
/* * __wt_evict_lru_page -- * Called by both eviction and application threads to evict a page. */ int __wt_evict_lru_page(WT_SESSION_IMPL *session, int is_app) { WT_BTREE *btree; WT_CACHE *cache; WT_DECL_RET; WT_PAGE *page; WT_REF *ref; if (is_app) WT_STAT_FAST_CONN_INCR(session, cache_eviction_app);
"cache" : {
"tracked dirty bytes in the cache" : 488305732,
"bytes currently in the cache" : 857590757,
"maximum bytes configured" : 1073741824,
"bytes read into cache" : 6992771243,
"bytes written from cache" : 4421343996,
"pages evicted by application threads" : 3938125731,
"checkpoint blocked page eviction" : 3,
"unmodified pages evicted" : 199580,
"page split during eviction deepened the tree" : 1,
"modified pages evicted" : 65810,
"pages selected for eviction unable to be evicted" : 941,
"pages evicted because they exceeded the in-memory maximum" : 400,
"pages evicted because they had chains of deleted items" : 2,
"failed eviction of pages that exceeded the in-memory maximum" : 0,
"hazard pointer blocked page eviction" : 20,
"internal pages evicted" : 0,
"maximum page size at eviction" : 42848801,
"eviction server candidate queue empty when topping up" : 1092,
"eviction server candidate queue not empty when topping up" : 11153,
"eviction server evicting pages" : 59,
"eviction server populating queue, but not evicting pages" : 12186,
"eviction server unable to reach eviction goal" : 0,
"pages split during eviction" : 3919,
"pages walked for eviction" : 9457046,
"in-memory page splits" : 133,
"tracked dirty pages in the cache" : 7550,
"pages currently held in the cache" : 14340,
"pages read into cache" : 279087,
"pages written from cache" : 221121
},
- duplicates
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SERVER-17020 Evictions by eviction server threads are reported as evictions by application threads
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- Closed
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