Message ID | 1522212741-15365-1-git-send-email-vdixit@akamai.com |
---|---|
State | Superseded |
Headers | show |
> On 28 Mar 2018, at 12:52, vdixit@akamai.com wrote: > > From: Vishwanath Dixit <vdixit@akamai.com> > > In write only mode, the TCP receive buffer keeps growing and eventually > becomes full. This results in zero tcp window size, which in turn causes > unwanted issues, like, terminated tcp connection. The issue is apparent > when http persistent connection is enabled in hls/dash streaming use > cases. To overcome this issue, the logic here reads and discards the data > from the tcp socket. > --- > libavformat/http.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/libavformat/http.c b/libavformat/http.c > index 983034f..e6d414b 100644 > --- a/libavformat/http.c > +++ b/libavformat/http.c > @@ -1627,6 +1627,13 @@ static int http_shutdown(URLContext *h, int flags) > ((flags & AVIO_FLAG_READ) && s->chunked_post && s->listen)) { > ret = ffurl_write(s->hd, footer, sizeof(footer) - 1); > ret = ret > 0 ? 0 : ret; > + /* flush the receive buffer when it is write only mode */ > + if (!(flags & AVIO_FLAG_READ)) { > + char buf[1024]; > + s->hd->flags |= AVIO_FLAG_NONBLOCK; > + ffurl_read(s->hd, buf, sizeof(buf)); ffurl_read have a int return value. 407 int ffurl_read(URLContext *h, unsigned char *buf, int size) 408 { 409 if (!(h->flags & AVIO_FLAG_READ)) 410 return AVERROR(EIO); 411 return retry_transfer_wrapper(h, buf, size, 1, h->prot->url_read); 412 } > + s->hd->flags &= ~AVIO_FLAG_NONBLOCK; > + } > s->end_chunked_post = 1; > } > > -- > 1.9.1 > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel Thanks Steven
On 3/28/18 11:00 AM, Steven Liu wrote: > > >> On 28 Mar 2018, at 12:52, vdixit@akamai.com wrote: >> >> From: Vishwanath Dixit <vdixit@akamai.com> >> >> In write only mode, the TCP receive buffer keeps growing and eventually >> becomes full. This results in zero tcp window size, which in turn causes >> unwanted issues, like, terminated tcp connection. The issue is apparent >> when http persistent connection is enabled in hls/dash streaming use >> cases. To overcome this issue, the logic here reads and discards the data >> from the tcp socket. >> --- >> libavformat/http.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/libavformat/http.c b/libavformat/http.c >> index 983034f..e6d414b 100644 >> --- a/libavformat/http.c >> +++ b/libavformat/http.c >> @@ -1627,6 +1627,13 @@ static int http_shutdown(URLContext *h, int flags) >> ((flags & AVIO_FLAG_READ) && s->chunked_post && s->listen)) { >> ret = ffurl_write(s->hd, footer, sizeof(footer) - 1); >> ret = ret > 0 ? 0 : ret; >> + /* flush the receive buffer when it is write only mode */ >> + if (!(flags & AVIO_FLAG_READ)) { >> + char buf[1024]; >> + s->hd->flags |= AVIO_FLAG_NONBLOCK; >> + ffurl_read(s->hd, buf, sizeof(buf)); > ffurl_read have a int return value. > > 407 int ffurl_read(URLContext *h, unsigned char *buf, int size) > 408 { > 409 if (!(h->flags & AVIO_FLAG_READ)) > 410 return AVERROR(EIO); > 411 return retry_transfer_wrapper(h, buf, size, 1, h->prot->url_read); > 412 } > > Thanks for the review comment. I have handled the return status of ffurl_read and have submitted a revised patch https://patchwork.ffmpeg.org/patch/8325/ >> + s->hd->flags &= ~AVIO_FLAG_NONBLOCK; >> + } >> s->end_chunked_post = 1; >> } >> >> -- >> 1.9.1 >> >> _______________________________________________ >> ffmpeg-devel mailing list >> ffmpeg-devel@ffmpeg.org >> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > Thanks > Steven > > > > >
diff --git a/libavformat/http.c b/libavformat/http.c index 983034f..e6d414b 100644 --- a/libavformat/http.c +++ b/libavformat/http.c @@ -1627,6 +1627,13 @@ static int http_shutdown(URLContext *h, int flags) ((flags & AVIO_FLAG_READ) && s->chunked_post && s->listen)) { ret = ffurl_write(s->hd, footer, sizeof(footer) - 1); ret = ret > 0 ? 0 : ret; + /* flush the receive buffer when it is write only mode */ + if (!(flags & AVIO_FLAG_READ)) { + char buf[1024]; + s->hd->flags |= AVIO_FLAG_NONBLOCK; + ffurl_read(s->hd, buf, sizeof(buf)); + s->hd->flags &= ~AVIO_FLAG_NONBLOCK; + } s->end_chunked_post = 1; }
From: Vishwanath Dixit <vdixit@akamai.com> In write only mode, the TCP receive buffer keeps growing and eventually becomes full. This results in zero tcp window size, which in turn causes unwanted issues, like, terminated tcp connection. The issue is apparent when http persistent connection is enabled in hls/dash streaming use cases. To overcome this issue, the logic here reads and discards the data from the tcp socket. --- libavformat/http.c | 7 +++++++ 1 file changed, 7 insertions(+)