The parallel insert performance test has recently started performing better for {w:1, j:true} writes than for {w:1, j:false} in runs with high concurrency (256, 512 or 1024 threads)

1024 threads, green j:false, pink j:true:

512 threads, pink j:false, orange j:true

32 threads, pink j:false, cyan j:true (j:false better as expected)

BF-24296 is the BF ticket on the switch point around the 3rd of February, which links to TIG-3391, an update to the C++ driver.