Fangrui Song 98e0b2cf70 [Support] Revert posix_fallocate in resize_file ... This reverts 3816c53f04 and removes follow-up fixups. The original intention was to show error earlier (posix_fallocate time) than later for ld.lld but it appears to cause some problems which make it not free. * FreeBSD ZFS: EINVAL, not too bad. * FreeBSD UFS: according to khng "devastatingly slow on freebsd because UFS on freebsd does not have preallocation support like illumos. It zero-fills." * NetBSD: maybe EOPNOTSUPP * Linux tmpfs: unless tmpfs is set up to use huge pages (requires CONFIG_TRANSPARENT_HUGE_PAGECACHE=y), I can consistently demonstrate ~300ms delay for a 1.4GiB output. * Linux ext4: I don't measure any benefit, either backed by a hard disk or by a file in tmpfs. * The current code organization of `defined(HAVE_POSIX_FALLOCATE)` costs us a macro dispatch for AIX. I think we should just remove it. I think if posix_fallocate ever finds demonstrable benefit, it is likely Linux specific and will not need HAVE_POSIX_FALLOCATE, and possibly opt-in by some specific programs. In a filesystem with CoW and compression, the ENOSPC benefit may be lost as well. Reviewed By: khng300 Differential Revision: https://reviews.llvm.org/D115957		2021-12-20 11:16:03 -08:00
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arcanist	[utils] Don't print username in arcanist clang format message	2021-05-14 14:33:00 +00:00
bazel	[Support] Revert posix_fallocate in resize_file	2021-12-20 11:16:03 -08:00