Change Details

Since 2023-03-14, performance of VE's getPageHTML function has become much slower on hewiki, with the median latency degrading from about 130ms to 600ms. See https://grafana.wikimedia.org/goto/F4rvB3fVz?orgId=1 Context: Hebrew Wikipedia (hewiki) is one of the wikis where we are testing out Visual Editor in "direct mode". This means Visual Editor is accessing Parsoid directly as a PHP library, and makes use of MediaWIki's parser cache, rather than relying on RESTbase.

Since 2023-03-14, performance of VE's getPageHTML function has become much slower on hewiki, with the median latency degrading from about 130ms to 600ms. See https://grafana.wikimedia.org/goto/F4rvB3fVz?orgId=1 Hypothesis: this is caused by a degraded parser cache hit rate. However, the hit rate seems fine globally. We do not have per-wiki stats for the parser cache hit rate, so we can't check whether it is degraded for hewiki for some reasons. Context: Hebrew Wikipedia (hewiki) is one of the wikis where we are testing out Visual Editor in "direct mode". This means Visual Editor is accessing Parsoid directly as a PHP library, and makes use of MediaWIki's parser cache, rather than relying on RESTbase.

Since 2023-03-14, performance of VE's getPageHTML function has become much slower on hewiki, with the median latency degrading from about 130ms to 600ms. See https://grafana.wikimedia.org/goto/F4rvB3fVz?orgId=1 Hypothesis: this is caused by a degraded parser cache hit rate. However, the hit rate seems fine globally. We do not have per-wiki stats for the parser cache hit rate, so we can't check whether it is degraded for hewiki for some reasons. Context: Hebrew Wikipedia (hewiki) is one of the wikis where we are testing out Visual Editor in "direct mode". This means Visual Editor is accessing Parsoid directly as a PHP library, and makes use of MediaWIki's parser cache, rather than relying on RESTbase.