Re: [PATCH v8 20/22] perf session: Load data directory files for analysis

[Jiri Olsa]

On Wed, Jun 30, 2021 at 06:54:59PM +0300, Alexey Bayduraev wrote:

SNIP

> +	while ((ret >= 0) && readers) {
> +		if (session_done())
> +			return 0;
> +
> +		if (rd[i].state.eof) {
> +			i = (i + 1) % session->nr_readers;
> +			continue;
> +		}
> +
> +		ret = reader__read_event(&rd[i], session, &prog);
> +		if (ret < 0)
> +			break;
> +		if (ret == READER_EOF) {
> +			ret = reader__mmap(&rd[i], session);
> +			if (ret < 0)
> +				goto out_err;
> +			if (ret == READER_EOF)
> +				readers--;
> +		}
> +
> +		/*
> +		 * Processing 10MBs of data from each reader in sequence,
> +		 * because that's the way the ordered events sorting works
> +		 * most efficiently.
> +		 */
> +		if (rd[i].state.size >= 10*1024*1024) {
> +			rd[i].state.size = 0;
> +			i = (i + 1) % session->nr_readers;
> +		}

hi,
so this was sort of hack to make this faster.. we need some
justification for this and make that configurable as well,
if we keep it

jirka