From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:41599) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UIdNF-0003IC-P6 for qemu-devel@nongnu.org; Thu, 21 Mar 2013 07:09:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UIdND-0001Et-1k for qemu-devel@nongnu.org; Thu, 21 Mar 2013 07:09:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43085) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UIdNC-0001En-Pf for qemu-devel@nongnu.org; Thu, 21 Mar 2013 07:09:30 -0400 Message-ID: <514AEAB0.2000108@redhat.com> Date: Thu, 21 Mar 2013 13:10:40 +0200 From: Orit Wasserman MIME-Version: 1.0 References: <1363856971-4601-1-git-send-email-owasserm@redhat.com> <1363856971-4601-8-git-send-email-owasserm@redhat.com> <514AD93E.1090205@redhat.com> In-Reply-To: <514AD93E.1090205@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC 07/12] Store the data to send also in iovec List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: quintela@redhat.com, chegu_vinod@hp.com, qemu-devel@nongnu.org, mst@redhat.com On 03/21/2013 11:56 AM, Paolo Bonzini wrote: > Il 21/03/2013 10:09, Orit Wasserman ha scritto: >> All data is still copied into the static buffer. >> >> Signed-off-by: Orit Wasserman >> --- >> savevm.c | 13 +++++++++++-- >> 1 file changed, 11 insertions(+), 2 deletions(-) >> >> diff --git a/savevm.c b/savevm.c >> index ec64533..d5834ca 100644 >> --- a/savevm.c >> +++ b/savevm.c >> @@ -114,6 +114,7 @@ void qemu_announce_self(void) >> /* savevm/loadvm support */ >> >> #define IO_BUF_SIZE 32768 >> +#define MAX_IOV_SIZE 64 > > You could use IOV_MAX, or min(IOV_MAX, 64). Sure The 64 should be tuned on a > good 10G network... You need to remember that iovec of 64 is equivalent to 32 guest pages which are 128K data. This is a large TCP packet that will be fragmented even with jumbo frames. I can make it configurable but not sure if it will be useful. Micheal, what do you think? Orit > > Paolo > >> struct QEMUFile { >> const QEMUFileOps *ops; >> @@ -129,6 +130,9 @@ struct QEMUFile { >> int buf_size; /* 0 when writing */ >> uint8_t buf[IO_BUF_SIZE]; >> >> + struct iovec iov[MAX_IOV_SIZE]; >> + unsigned int iovcnt; >> + >> int last_error; >> }; >> >> @@ -546,6 +550,7 @@ static void qemu_fflush(QEMUFile *f) >> f->pos += f->buf_index; >> } >> f->buf_index = 0; >> + f->iovcnt = 0; >> } >> if (ret < 0) { >> qemu_file_set_error(f, ret); >> @@ -638,12 +643,14 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size) >> if (l > size) >> l = size; >> memcpy(f->buf + f->buf_index, buf, l); >> + f->iov[f->iovcnt].iov_base = f->buf + f->buf_index; >> + f->iov[f->iovcnt++].iov_len = l; >> f->is_write = 1; >> f->buf_index += l; >> f->bytes_xfer += l; >> buf += l; >> size -= l; >> - if (f->buf_index >= IO_BUF_SIZE) { >> + if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) { >> qemu_fflush(f); >> if (qemu_file_get_error(f)) { >> break; >> @@ -667,8 +674,10 @@ void qemu_put_byte(QEMUFile *f, int v) >> f->buf[f->buf_index++] = v; >> f->is_write = 1; >> f->bytes_xfer += 1; >> + f->iov[f->iovcnt].iov_base = f->buf + (f->buf_index - 1); >> + f->iov[f->iovcnt++].iov_len = 1; >> >> - if (f->buf_index >= IO_BUF_SIZE) { >> + if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) { >> qemu_fflush(f); >> } >> } >> >