diff options
Diffstat (limited to 'src/cache/cache_las.c')
| -rw-r--r-- | src/cache/cache_las.c | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/src/cache/cache_las.c b/src/cache/cache_las.c index 41da4225f3a..a2233514223 100644 --- a/src/cache/cache_las.c +++ b/src/cache/cache_las.c @@ -1,5 +1,5 @@ /*- - * Copyright (c) 2014-2016 MongoDB, Inc. + * Copyright (c) 2014-2017 MongoDB, Inc. * Copyright (c) 2008-2014 WiredTiger, Inc. * All rights reserved. * @@ -140,8 +140,9 @@ __wt_las_set_written(WT_SESSION_IMPL *session) conn->las_written = true; /* - * Push the flag: unnecessary, but from now page reads must deal - * with lookaside table records, and we only do the write once. + * Future page reads must deal with lookaside table records. + * No write could be cached until a future read might matter, + * the barrier is more documentation than requirement. */ WT_FULL_BARRIER(); } @@ -291,8 +292,7 @@ __wt_las_sweep(WT_SESSION_IMPL *session) WT_DECL_ITEM(las_key); WT_DECL_RET; WT_ITEM *key; - uint64_t cnt, las_counter, las_txnid; - int64_t remove_cnt; + uint64_t cnt, las_counter, las_txnid, remove_cnt; uint32_t las_id, session_flags; int notused; @@ -341,7 +341,7 @@ __wt_las_sweep(WT_SESSION_IMPL *session) * blocks in the cache in order to get rid of them, and slowly review * lookaside blocks that have already been evicted. */ - cnt = (uint64_t)WT_MAX(100, conn->las_record_cnt / 30); + cnt = WT_MAX(100, conn->las_record_cnt / 30); /* Discard pages we read as soon as we're done with them. */ F_SET(session, WT_SESSION_NO_CACHE); @@ -389,14 +389,13 @@ err: __wt_buf_free(session, key); WT_TRET(__wt_las_cursor_close(session, &cursor, session_flags)); /* - * If there were races to remove records, we can over-count. All - * arithmetic is signed, so underflow isn't fatal, but check anyway so - * we don't skew low over time. + * If there were races to remove records, we can over-count. Underflow + * isn't fatal, but check anyway so we don't skew low over time. */ - if (remove_cnt > S2C(session)->las_record_cnt) - S2C(session)->las_record_cnt = 0; + if (remove_cnt > conn->las_record_cnt) + conn->las_record_cnt = 0; else if (remove_cnt > 0) - (void)__wt_atomic_subi64(&conn->las_record_cnt, remove_cnt); + (void)__wt_atomic_sub64(&conn->las_record_cnt, remove_cnt); F_CLR(session, WT_SESSION_NO_CACHE); |