On Mon, 18 Mar 2019, Bob Friesenhahn wrote:
Based on my understanding of plockstat output (reported times are described as "Average duration of an event, in nanoseconds"), libumem is taking 28.6, 47.8, or 67.1 *milliseconds* per contested lock for memory requests related to posix_memalign(). This is an astonishing amount of time.
If I remove use of posix_memalign() and instead use an aligned memory implementation based on malloc() with an added header used by a special matching freeing function, then the longest umem-related time I see is vmem_sbrk_alloc, which takes 8,052,736 nanoseconds or sometimes 23,555,227 nanoseconds. Otherwise, umem is largely gone from the radar. Contention issues due to design issues in my own code then become the prominent ones.
Bob -- Bob Friesenhahn [email protected], http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ Public Key, http://www.simplesystems.org/users/bfriesen/public-key.txt ------------------------------------------ illumos: illumos-discuss Permalink: https://illumos.topicbox.com/groups/discuss/T30dd2eceb8a069b3-M05b77eab2a1ec956a2c6f9a2 Delivery options: https://illumos.topicbox.com/groups/discuss/subscription
