pgsql: Does it help to wait before reattaching?

Does it help to wait before reattaching?

Revert the map/unmap dance I tried in commit 73042b8d1; that helps
not at all.

Instead, speculate that the unwanted allocation is being done on
another thread, and thus timing variations explain the apparent
unpredictability. Temporarily add a 1-second sleep before the
VirtualFree call, in hopes that any such other threads will
quiesce and not jog our elbow.

This is obviously not a desirable long-term fix, but as a means of
investigation it seems useful.

Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/23078689a9921968ac0873b017be6e7f772f10bc

Modified Files
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src/backend/port/win32_shmem.c | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)