On jeu., juil. 06, 2023 at 13:00, Tom Rini <tr...@konsulko.com> wrote:
> On Thu, Jul 06, 2023 at 11:43:13AM +0200, Mattijs Korpershoek wrote: >> On lun., juin 19, 2023 at 10:21, Mattijs Korpershoek >> <mkorpersh...@baylibre.com> wrote: >> >> > Hi Qianfan, >> > >> > Thank you for your review. >> > >> > On lun., juin 19, 2023 at 14:19, qianfan <qianfangui...@163.com> wrote: >> > >> >> 在 2023/6/16 21:26, Mattijs Korpershoek 写道: >> >>> Commit 62649165cb02 ("lib: sparse: Make CHUNK_TYPE_RAW buffer aligned") >> >>> fixed cache alignment for systems with a D-CACHE. >> >>> >> >>> However it introduced some performance regressions [1] on system >> >>> flashing huge images, such as Android. >> >>> >> >>> On AM62x SK EVM, we also observe such performance penalty: >> >>> Sending sparse 'super' 1/2 (768793 KB) OKAY [ 23.954s] >> >>> Writing 'super' OKAY [ 75.926s] >> >>> Sending sparse 'super' 2/2 (629819 KB) OKAY [ 19.641s] >> >>> Writing 'super' OKAY [ 62.849s] >> >>> Finished. Total time: 182.474s >> >>> >> >>> The reason for this is that we use an arbitrary small buffer >> >>> (info->blksz * 100) for transferring. >> >>> >> >>> Fix it by using a bigger buffer (info->blksz * blkcnt) as suggested in >> >>> the original's patch review [2]. >> >>> >> >>> With this patch, performance impact is mitigated: >> >>> Sending sparse 'super' 1/2 (768793 KB) OKAY [ 24.006s] >> >>> Writing 'super' OKAY [ 15.920s] >> >>> Sending sparse 'super' 2/2 (629819 KB) OKAY [ 19.651s] >> >>> Writing 'super' OKAY [ 14.665s] >> >>> Finished. Total time: 74.346s >> >>> >> >>> [1] >> >>> https://lore.kernel.org/r/20221118121323.4009193-1-gary.bis...@boundarydevices.com >> >>> [2] >> >>> https://lore.kernel.org/r/all/43e4c17c-4483-ec8e-f843-9b4c5569b...@seco.com/ >> >>> >> >>> Fixes: 62649165cb02 ("lib: sparse: Make CHUNK_TYPE_RAW buffer aligned") >> >>> Signed-off-by: Mattijs Korpershoek <mkorpersh...@baylibre.com> >> >>> --- >> >>> lib/image-sparse.c | 2 +- >> >>> 1 file changed, 1 insertion(+), 1 deletion(-) >> >>> >> >>> diff --git a/lib/image-sparse.c b/lib/image-sparse.c >> >>> index 5ec0f94ab3eb..25aed0604192 100644 >> >>> --- a/lib/image-sparse.c >> >>> +++ b/lib/image-sparse.c >> >>> @@ -55,7 +55,7 @@ static lbaint_t write_sparse_chunk_raw(struct >> >>> sparse_storage *info, >> >>> void *data, >> >>> char *response) >> >>> { >> >>> - lbaint_t n = blkcnt, write_blks, blks = 0, aligned_buf_blks = >> >>> 100; >> >>> + lbaint_t n = blkcnt, write_blks, blks = 0, aligned_buf_blks = >> >>> blkcnt; >> >> Hi: >> >> >> >> It's a good point that this code report the performance was affected by >> >> write large small >> >> mmc blks, not memory copy. >> > >> > I believe memory copy also affects performance, but in my case, >> > it has less impact than small mmc blks. >> > >> > With 62649165cb02 reverted: >> > Sending sparse 'super' 1/2 (768793 KB) OKAY [ 23.947s] >> > Writing 'super' OKAY [ 12.983s] >> > Sending sparse 'super' 2/2 (629819 KB) OKAY [ 19.600s] >> > Writing 'super' OKAY [ 12.796s] >> > Finished. Total time: 69.430s >> > >> > With aligned_buf_blks = blkcnt: >> > Sending sparse 'super' 1/2 (768793 KB) OKAY [ 24.072s] >> > Writing 'super' OKAY [ 16.177s] >> > Sending sparse 'super' 2/2 (629819 KB) OKAY [ 19.681s] >> > Writing 'super' OKAY [ 14.845s] >> > Finished. Total time: 74.919s >> > >> >> >> >> And I can not make sure whether memalign can always alloc such huge >> >> memory when we change the >> >> aligned_buf_blks to blkcnt. >> > >> > Could you clarify the concern here? I've dumped blkcnt for my board >> > (AM62x SK EVK) and the biggest blkcnt I found was: 131072 >> > >> > With info->blksz = 512, this gives me: 512 * 131072 = 67108864 >> > >> > Which is a memalign (memory alloc) of 64MB. Is 64MB really that big? (I >> > don't realize it's that much) >> > >> >> >> >> Could you please set aligned_buf_blks to FASTBOOT_MAX_BLK_WRITE(16384) >> >> and test again? >> > >> > With aligned_buf_blks = FASTBOOT_MAX_BLK_WRITE(16384): >> > Sending sparse 'super' 1/2 (768793 KB) OKAY [ 23.912s] >> > Writing 'super' OKAY [ 15.780s] >> > Sending sparse 'super' 2/2 (629819 KB) OKAY [ 19.581s] >> > Writing 'super' OKAY [ 17.192s] >> > Finished. Total time: 76.569s >> > >> > So using FASTBOOT_MAX_BLK_WRITE is slightly worse than using blkcnt. >> > But allocations (for blksz = 512) are smaller: 8MB instead of 64MB in my >> > example. >> > >> > I can spin up a v2 with FASTBOOT_MAX_BLK_WRITE but i'm waiting a little >> > more feedback before doing so. >> >> Hi Marek, Tom, >> >> What's your take on this ? Can we keep blkcnt or should I respin using >> FASTBOOT_MAX_BLK_WRITE ? >> >> I have also tested this on VIM3, on >> U-Boot 2023.07-rc6-00003-g923de765ee1a: >> >> Sending sparse 'super' 1/13 (114684 KB) OKAY [ 5.442s] >> Writing 'super' OKAY [ 5.791s] >> Sending sparse 'super' 2/13 (114684 KB) OKAY [ 5.706s] >> Writing 'super' OKAY [ 5.607s] >> Sending sparse 'super' 3/13 (114684 KB) OKAY [ 5.468s] >> Writing 'super' OKAY [ 5.835s] >> Sending sparse 'super' 4/13 (114684 KB) OKAY [ 5.703s] >> Writing 'super' OKAY [ 5.618s] >> Sending sparse 'super' 5/13 (114684 KB) OKAY [ 6.176s] >> Writing 'super' OKAY [ 5.421s] >> Sending sparse 'super' 6/13 (104176 KB) OKAY [ 5.204s] >> Writing 'super' OKAY [ 5.199s] >> Sending sparse 'super' 7/13 (108856 KB) OKAY [ 5.456s] >> Writing 'super' OKAY [ 5.290s] >> Sending sparse 'super' 8/13 (114684 KB) OKAY [ 6.122s] >> Writing 'super' OKAY [ 5.838s] >> Sending sparse 'super' 9/13 (114684 KB) OKAY [ 5.951s] >> Writing 'super' OKAY [ 5.857s] >> Sending sparse 'super' 10/13 (100980 KB) OKAY [ 4.902s] >> Writing 'super' OKAY [ 4.749s] >> Sending sparse 'super' 11/13 (114681 KB) OKAY [ 6.041s] >> Writing 'super' OKAY [ 5.779s] >> Sending sparse 'super' 12/13 (107212 KB) OKAY [ 5.174s] >> Writing 'super' OKAY [ 6.587s] >> Sending sparse 'super' 13/13 (71496 KB) OKAY [ 3.717s] >> Writing 'super' OKAY [ 3.744s] >> Finished. Total time: 142.578s >> >> With this patch: >> Sending sparse 'super' 1/13 (114684 KB) OKAY [ 7.149s] >> Writing 'super' OKAY [ 1.639s] >> Sending sparse 'super' 2/13 (114684 KB) OKAY [ 6.993s] >> Writing 'super' OKAY [ 1.713s] >> Sending sparse 'super' 3/13 (114684 KB) OKAY [ 7.029s] >> Writing 'super' OKAY [ 1.107s] >> Sending sparse 'super' 4/13 (114684 KB) OKAY [ 7.027s] >> Writing 'super' OKAY [ 0.162s] >> Sending sparse 'super' 5/13 (114684 KB) OKAY [ 6.930s] >> Writing 'super' OKAY [ 1.643s] >> Sending sparse 'super' 6/13 (104176 KB) OKAY [ 6.253s] >> Writing 'super' OKAY [ 2.348s] >> Sending sparse 'super' 7/13 (108856 KB) OKAY [ 6.346s] >> Writing 'super' OKAY [ 0.723s] >> Sending sparse 'super' 8/13 (114684 KB) OKAY [ 6.715s] >> Writing 'super' OKAY [ 2.848s] >> Sending sparse 'super' 9/13 (114684 KB) OKAY [ 6.888s] >> Writing 'super' OKAY [ 1.928s] >> Sending sparse 'super' 10/13 (100980 KB) OKAY [ 5.979s] >> Writing 'super' OKAY [ 1.178s] >> Sending sparse 'super' 11/13 (114681 KB) OKAY [ 6.822s] >> Writing 'super' OKAY [ 2.652s] >> Sending sparse 'super' 12/13 (107212 KB) OKAY [ 6.414s] >> Writing 'super' OKAY [ 5.109s] >> Sending sparse 'super' 13/13 (71496 KB) OKAY [ 4.238s] >> Writing 'super' OKAY [ 0.252s] >> Finished. Total time: 108.151s >> >> It's probably too late for v2023.07 to pick this up but can we consider >> taking it for next? > > I was waiting for a v2, and yes, it's too late for v2023.07. Sorry for > not being clear enough. Oh, sorry I did not understand that. I understand for v2023.07. Thank you for the quick answer. Will send a v2 shortly using FASTBOOT_MAX_BLK_WRITE. > > -- > Tom