From 8c5200b5689e9612a59c12d28e71a716efac2830 Mon Sep 17 00:00:00 2001
From: Richard Nyberg <rnyberg@murmeldjur.se>
Date: Mon, 6 Nov 2006 08:48:22 +0000
Subject: [PATCH] Instead of immediately reading all data a peer requests into
outgoing net buffers, we put placeholder buffers on the list and fill them as
they are needed. At most 4 blocks will be filled per peer we upload to. This
number should probably be made tunable or be based on SO_SNDBUF or something.
Anyway, this should lower btpd's memory usage if one has many uploads.
---
btpd/net.c | 18 ++++++++++++++++++
btpd/net_buf.c | 19 +++++++++++++++++--
btpd/net_buf.h | 5 ++++-
btpd/peer.c | 17 +++++++----------
4 files changed, 46 insertions(+), 13 deletions(-)
diff --git a/btpd/net.c b/btpd/net.c
index 17271f0..5551221 100644
--- a/btpd/net.c
+++ b/btpd/net.c
@@ -134,6 +134,8 @@ net_read32(const void *buf)
| (uint16_t)*(p + 2) << 8 | *(p + 3);
}
+#define BLOCK_MEM_COUNT 4
+
static unsigned long
net_write(struct peer *p, unsigned long wmax)
{
@@ -143,13 +145,29 @@ net_write(struct peer *p, unsigned long wmax)
int limited;
ssize_t nwritten;
unsigned long bcount;
+ int block_count = 0;
limited = wmax > 0;
niov = 0;
assert((nl = BTPDQ_FIRST(&p->outq)) != NULL);
+ if (nl->nb->type == NB_TORRENTDATA)
+ block_count = 1;
while ((niov < IOV_MAX && nl != NULL
&& (!limited || (limited && wmax > 0)))) {
+ if (nl->nb->type == NB_PIECE) {
+ if (block_count >= BLOCK_MEM_COUNT)
+ break;
+ struct net_buf *tdata = BTPDQ_NEXT(nl, entry)->nb;
+ if (tdata->buf == NULL) {
+ if (nb_torrentdata_fill(tdata, p->n->tp, nb_get_index(nl->nb),
+ nb_get_begin(nl->nb), nb_get_length(nl->nb)) != 0) {
+ peer_kill(p);
+ return 0;
+ }
+ }
+ block_count++;
+ }
if (niov > 0) {
iov[niov].iov_base = nl->nb->buf;
iov[niov].iov_len = nl->nb->len;
diff --git a/btpd/net_buf.c b/btpd/net_buf.c
index 6827c9c..1206ef8 100644
--- a/btpd/net_buf.c
+++ b/btpd/net_buf.c
@@ -90,13 +90,28 @@ nb_create_piece(uint32_t index, uint32_t begin, size_t blen)
}
struct net_buf *
-nb_create_torrentdata(char *block, size_t blen)
+nb_create_torrentdata(void)
{
struct net_buf *out;
- out = nb_create_set(NB_TORRENTDATA, block, blen, kill_buf_free);
+ out = nb_create_set(NB_TORRENTDATA, NULL, 0, kill_buf_no);
return out;
}
+int
+nb_torrentdata_fill(struct net_buf *nb, struct torrent *tp, uint32_t index,
+ uint32_t begin, uint32_t length)
+{
+ int err;
+ uint8_t *content;
+ assert(nb->type == NB_TORRENTDATA && nb->buf == NULL);
+ if ((err = cm_get_bytes(tp, index, begin, length, &content)) != 0)
+ return err;
+ nb->buf = content;
+ nb->len = length;
+ nb->kill_buf = kill_buf_free;
+ return 0;
+}
+
struct net_buf *
nb_create_request(uint32_t index, uint32_t begin, uint32_t length)
{
diff --git a/btpd/net_buf.h b/btpd/net_buf.h
index a04bcd7..aa9755c 100644
--- a/btpd/net_buf.h
+++ b/btpd/net_buf.h
@@ -36,7 +36,7 @@ struct peer;
struct net_buf *nb_create_keepalive(void);
struct net_buf *nb_create_piece(uint32_t index, uint32_t begin, size_t blen);
-struct net_buf *nb_create_torrentdata(char *block, size_t blen);
+struct net_buf *nb_create_torrentdata(void);
struct net_buf *nb_create_request(uint32_t index,
uint32_t begin, uint32_t length);
struct net_buf *nb_create_cancel(uint32_t index,
@@ -51,6 +51,9 @@ struct net_buf *nb_create_bitfield(struct torrent *tp);
struct net_buf *nb_create_bitdata(struct torrent *tp);
struct net_buf *nb_create_shake(struct torrent *tp);
+int nb_torrentdata_fill(struct net_buf *nb, struct torrent *tp, uint32_t index,
+ uint32_t begin, uint32_t length);
+
int nb_drop(struct net_buf *nb);
void nb_hold(struct net_buf *nb);
diff --git a/btpd/peer.c b/btpd/peer.c
index cb34585..864acb0 100644
--- a/btpd/peer.c
+++ b/btpd/peer.c
@@ -489,16 +489,13 @@ peer_on_request(struct peer *p, uint32_t index, uint32_t begin,
btpd_log(BTPD_L_MSG, "received request(%u,%u,%u) from %p\n",
index, begin, length, p);
if ((p->flags & PF_NO_REQUESTS) == 0) {
- uint8_t *content;
- if (cm_get_bytes(p->n->tp, index, begin, length, &content) == 0) {
- peer_send(p, nb_create_piece(index, begin, length));
- peer_send(p, nb_create_torrentdata(content, length));
- p->npiece_msgs++;
- if (p->npiece_msgs >= MAXPIECEMSGS) {
- peer_send(p, nb_create_choke());
- peer_send(p, nb_create_unchoke());
- p->flags |= PF_NO_REQUESTS;
- }
+ peer_send(p, nb_create_piece(index, begin, length));
+ peer_send(p, nb_create_torrentdata());
+ p->npiece_msgs++;
+ if (p->npiece_msgs >= MAXPIECEMSGS) {
+ peer_send(p, nb_create_choke());
+ peer_send(p, nb_create_unchoke());
+ p->flags |= PF_NO_REQUESTS;
}
}
}