@@ -25,7 +25,7 @@
static void explain(void)
{
- fprintf(stderr, "Usage: ... [p|b]fifo [ limit NUMBER ]\n");
+ fprintf(stderr, "Usage: ... <[p|b]fifo | pfifo_head_drop> [ limit NUMBER ]\n");
}
static int fifo_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n)
@@ -89,6 +89,12 @@ struct qdisc_util pfifo_qdisc_util = {
.print_qopt = fifo_print_opt,
};
+struct qdisc_util pfifo_head_drop_qdisc_util = {
+ .id = "pfifo_head_drop",
+ .parse_qopt = fifo_parse_opt,
+ .print_qopt = fifo_print_opt,
+};
+
extern int prio_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt);
struct qdisc_util pfifo_fast_qdisc_util = {
.id = "pfifo_fast",
This adds the required changes to gain access to the head drop classfull queuing discipline named pfifo_head_drop. In difference to pfifo or pfifo_fast this queuing discipline will drop the first packet in the case of queue congestion. As a result the queue contain always the freshest packets. To replace the current a root queueing discipline for eth0: $ tc qdisc replace dev eth0 root pfifo_head_drop And show statistics: $ tc -s qdisc show dev eth0 Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net> --- tc/q_fifo.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-)