Re: [PATCH v5 07/10] perf record: implement -z,--compression_level=n option and compression

[Jiri Olsa]

On Fri, Mar 01, 2019 at 06:58:32PM +0300, Alexey Budankov wrote:

SNIP

> +static size_t record__zstd_compress(void *data, void *dst, size_t dst_size,
> +		void *src, size_t src_size)
> +{
> +	size_t compressed;
> +	struct perf_session *session = data;
> +	/* maximum size of record data size (2^16 - 1 - header) */
> +	const size_t max_record_size = (1 << 8 * sizeof(u16)) -

I dont follow this calculation, could you just use PERF_SAMPLE_MAX_SIZE?

jirka

> +					1 - sizeof(struct compressed_event);
> +

SNIP