[bitcoin-dev] Versionbits BIP (009) minor revision proposal.

[Rusty Russell <rusty@rustcorp.com.au>]

Hi all,

        Pieter and Eric pointed out that the current BIP has miners
turning off the bit as soon as it's locked in (75% testnet / 95%
mainnet).  It's better for them to keep setting the bit until activation
(2016 blocks later), so network adoption is visible.

I'm not proposing another suggestion, though I note it for future:
miners keep setting the bit for another 2016 blocks after activation,
and have a consensus rule that rejects blocks without the bit.  That
would "force" upgrades on those last miners.  I feel we should see how
this works first.

Cheers,
Rusty.

diff --git a/bip-0009.mediawiki b/bip-0009.mediawiki
index c17ca15..b160810 100644
--- a/bip-0009.mediawiki
+++ b/bip-0009.mediawiki
@@ -37,14 +37,15 @@ retarget period.
 Software which supports the change should begin by setting B in all blocks
 mined until it is resolved.
 
-    if (BState == defined) {
+    if (BState != activated && BState != failed) {
         SetBInBlock();
     }
 
 '''Success: Lock-in Threshold'''
 If bit B is set in 1916 (1512 on testnet) or
 more of the 2016 blocks within a retarget period, it is considered
-''locked-in''.  Miners should stop setting bit B.
+''locked-in''.  Miners should continue setting bit B, so uptake is
+visible.
 
     if (NextBlockHeight % 2016 == 0) {
         if (BState == defined && Previous2016BlocksCountB() >= 1916) {
@@ -57,7 +58,7 @@ more of the 2016 blocks within a retarget period, it is considered
 The consensus rules related to ''locked-in'' soft fork will be enforced in
 the second retarget period; ie. there is a one retarget period in
 which the remaining 5% can upgrade.  At the that activation block and
-after, the bit B may be reused for a different soft fork.
+after, miners should stop setting bit B, which may be reused for a different soft fork.
 
     if (BState == locked-in && NextBlockHeight == BActiveHeight) {
         BState = activated;