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What is the smear interval for a leap smear?

How does leap smearing work in NTP?

  • Due to the reasons mentioned above, some support for leap smearing has recently been implemented in ntpd. This means that to insert a leap second an NTP server adds a certain increasing "smear" offset to the real UTC time sent to its clients, so that after some predefined interval the leap second offset is compensated.

What is the difference between utcutc-SLS and Google's second leap smear?

  • UTC-SLS is a linear smear over 1,000 s before the leap (23:43:20 to 00:00:00). Google's 2008 smear was a 20-hour cosine smear before the leap (04:00:00 to 00:00:00). This was the only time we used a cosine smear. Google's second leap smear was a 20-hour linear smear centered on the leap.

What is a leap second?

  • Leap seconds are periodical adjustments that result in the addition of a second to the Coordinated Universal Time ( UTC) to keep UTC time synchronized with the Earth’s ever-slowing rotation. These leap seconds can create issues for IT systems and software code that require time synchronization with other systems for accurate results.

image-What is the smear interval for a leap smear?
image-What is the smear interval for a leap smear?
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