pxelinux: be more aggressive about retransmitting ACKs

Some PXE stacks drop packets on transmit on a regular basis.  Avoid
severe slowdowns by being much more aggressive about ACK
retransmissions.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/core/pxelinux.asm b/core/pxelinux.asm
index 2e3d662..f7f60b5 100644 (file)
--- a/core/pxelinux.asm
+++ b/core/pxelinux.asm
@@ -39,8 +39,8 @@ MAX_OPEN_LG2  equ 5                   ; log2(Max number of open sockets)
 MAX_OPEN       equ (1 << MAX_OPEN_LG2)
 PKTBUF_SIZE    equ (65536/MAX_OPEN)    ; Per-socket packet buffer size
 TFTP_PORT      equ htons(69)           ; Default TFTP port
-PKT_RETRY      equ 6                   ; Packet transmit retry count
-PKT_TIMEOUT    equ 12                  ; Initial timeout, timer ticks @ 55 ms
+PKT_RETRY      equ 10                  ; Packet transmit retry count
+PKT_TIMEOUT    equ 2                   ; Initial timeout, timer ticks @ 55 ms
 ; Desired TFTP block size
 ; For Ethernet MTU is normally 1500.  Unfortunately there seems to
 ; be a fair number of networks with "substandard" MTUs which break.