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charset=utf-8 Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 8D4BA40007 X-Stat-Signature: dn6w8gqkzxig3iy7qex37adtmidfbgh6 X-HE-Tag: 1742327681-373106 X-HE-Meta: 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 2yThXGJu 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Mar 18, 2025 at 05:43:41PM +0000, Ryan Roberts wrote: > create_pagecache_thp_and_fd() was previously writing a file sized at > twice the PMD size by making a per-byte write syscall. This was quite > slow when the PMD size is 4M, but completely intolerable for 32M (PMD > size for arm64's 16K page size), and 512M (PMD size for arm64's 64K page > size). > > The byte pattern has a 256 byte period, so let's create a 1K buffer and > fill it with exactly 4 periods. Then we can write the buffer as many > times as is required to fill the file. This makes things much more > tolerable. > > The test now passes for 16K page size. It still fails for 64K page size > because MAX_PAGECACHE_ORDER is too small for 512M folio size (I think). > > Signed-off-by: Ryan Roberts Acked-by: Peter Xu -- Peter Xu