From 1de80624466405bccdbc4607d71cd249320da3f1 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 31 Oct 2017 10:50:03 -0600 Subject: [PATCH] Default buffer_compress_chunk to 512 This makes us behave better out of the box, for the cases where people use bigger block sizes. Without this change and if the user set buffer_compress_percentage=50 and bs=128k, then we'd have 64k of zeroes at the end. This is probably not what the user expects. Signed-off-by: Jens Axboe --- HOWTO | 2 +- fio.1 | 2 +- options.c | 1 + 3 files changed, 3 insertions(+), 2 deletions(-) diff --git a/HOWTO b/HOWTO index e510e18c..419fa737 100644 --- a/HOWTO +++ b/HOWTO @@ -1464,7 +1464,7 @@ Buffers and memory followed by the remaining zeroed. With this set to some chunk size smaller than the block size, fio can alternate random and zeroed data throughout the I/O buffer. This is particularly useful when bigger block sizes are used - for a job. + for a job. Defaults to 512. .. option:: buffer_pattern=str diff --git a/fio.1 b/fio.1 index 8e983724..63d32a52 100644 --- a/fio.1 +++ b/fio.1 @@ -1252,7 +1252,7 @@ will provide \fBbuffer_compress_percentage\fR of blocksize random data, followed by the remaining zeroed. With this set to some chunk size smaller than the block size, fio can alternate random and zeroed data throughout the I/O buffer. This is particularly useful when bigger block sizes are used -for a job. +for a job. Defaults to 512. .TP .BI buffer_pattern \fR=\fPstr If set, fio will fill the I/O buffers with this pattern or with the contents diff --git a/options.c b/options.c index 5813a66b..e8d1a3ab 100644 --- a/options.c +++ b/options.c @@ -4067,6 +4067,7 @@ struct fio_option fio_options[FIO_MAX_OPTS] = { .parent = "buffer_compress_percentage", .hide = 1, .help = "Size of compressible region in buffer", + .def = "512", .interval = 256, .category = FIO_OPT_C_IO, .group = FIO_OPT_G_IO_BUF, -- 2.25.1