Re: [PATCH v2 2/4] perf record: implement -z=<level> and --mmap-flush=<thres> options

From: Jiri Olsa
Date: Tue Feb 12 2019 - 08:08:34 EST


On Mon, Feb 11, 2019 at 11:22:38PM +0300, Alexey Budankov wrote:

SNIP

> - if (rec->opts.nr_cblocks > nr_cblocks_max)
> - rec->opts.nr_cblocks = nr_cblocks_max;
> - if (verbose > 0)
> - pr_info("nr_cblocks: %d\n", rec->opts.nr_cblocks);
> + if (rec->opts.comp_level > 22)
> + rec->opts.comp_level = 0;
> + if (record__comp_enabled(rec) && !rec->opts.nr_cblocks) {
> + /*
> + * Allocate aio.data[0] buffer for compression.
> + */
> + rec->opts.nr_cblocks = -1;
> + }

I assume you're using aio.data[0] as a buffer for non-aio case
as compression buffer.. if that's the case, please dont do that
and use separate buffer for that

jirka