On Tue, Sep 25, 2018 at 1:39 PM, Joel Fernandes <joelaf@xxxxxxxxxx> wrote: > On Tue, Sep 25, 2018 at 1:37 PM, Joel Fernandes <joelaf@xxxxxxxxxx> wrote: >> On Sun, Sep 23, 2018 at 8:33 AM, Sai Prakash Ranjan >> <saiprakash.ranjan@xxxxxxxxxxxxxx> wrote: >>> On 9/22/2018 10:07 PM, Sai Prakash Ranjan wrote: >>>> >>>> On 9/22/2018 2:35 PM, Joel Fernandes wrote: >>>>> >>>>> On Sat, Sep 8, 2018 at 4:28 PM Sai Prakash Ranjan >>>>> <saiprakash.ranjan@xxxxxxxxxxxxxx> wrote: >>>>>> >>>>>> >>>>>> + >>>>>> + trace_seq_init(&iter->seq); >>>>>> + iter->ent = fbuffer->entry; >>>>>> + event_call->event.funcs->trace(iter, 0, event); >>>>>> + trace_seq_putc(&iter->seq, 0); >>>>> >>>>> >>>>> Would it be possible to store the binary trace record in the pstore >>>>> buffer instead of outputting text? I suspect that will both be faster >>>>> and less space. >>>>> >>>> >>>> I will try this and come back. >>>> >>> >>> Hi Joel, >>> >>> I removed trace_seq_putc and there is some improvement seen: 203 MB/s >>> >>> # dd if=/dev/zero of=/dev/null status=progress >>> 12207371264 bytes (12 GB, 11 GiB) copied, 60 s, 203 MB/s^C >>> 24171926+0 records in >>> 24171926+0 records out >>> 12376026112 bytes (12 GB, 12 GiB) copied, 60.8282 s, 203 MB/s >>> >>> This seems good when compared to 190 MB/s seen previously. >>> If this is Ok, then I will spin v2 with changes suggested. >> >> Sorry for slow reply, yes that sounds good and a worthwhile perf improvement. >> > > Well so I think you should still not use spinlock to synchronize and > split the buffer. You could expand pstore_record to have a ts field or > introduce a new API like ->write_percpu instead of write, or > something. But I strongly feel you should lock. For ftrace function Aargh, I meant you should *not* lock :-)
