/// <summary>
/// Shift log head address to prune memory foorprint of hybrid log
/// </summary>
/// <param name="newHeadAddress">Address to shift head until</param>
/// <param name="wait">Wait for operation to complete (may involve page flushing and closing)</param>
public void ShiftHeadAddress(long newHeadAddress, bool wait)
{
// First shift read-only
// Force wait so that we do not close unflushed page
ShiftReadOnlyAddress(newHeadAddress, true);
// Then shift head address
if (!fht.epoch.ThisInstanceProtected())
{
try
{
fht.epoch.Resume();
allocator.ShiftHeadAddress(newHeadAddress);
}
finally
{
fht.epoch.Suspend();
}
while (wait && allocator.SafeHeadAddress < newHeadAddress)
{
Thread.Yield();
}
}
else
{
allocator.ShiftHeadAddress(newHeadAddress);
while (wait && allocator.SafeHeadAddress < newHeadAddress)
{
fht.epoch.ProtectAndDrain();
}
}
}
/// <summary>
/// Shift log head address to prune memory foorprint of hybrid log
/// </summary>
/// <param name="newHeadAddress">Address to shift head until</param>
/// <param name="wait">Wait to ensure shift is registered (may involve page flushing)</param>
/// <returns>When wait is false, this tells whether the shift to newHeadAddress was successfully registered with FASTER</returns>
public bool ShiftHeadAddress(long newHeadAddress, bool wait)
{
// First shift read-only
ShiftReadOnlyAddress(newHeadAddress, wait);
// Then shift head address
var updatedHeadAddress = allocator.ShiftHeadAddress(newHeadAddress);
return(updatedHeadAddress >= newHeadAddress);
}
/// <summary>
/// Shift log head address to prune memory foorprint of hybrid log
/// </summary>
/// <param name="newHeadAddress">Address to shift head until</param>
/// <param name="wait">Wait to ensure shift is registered (may involve page flushing)</param>
/// <returns>When wait is false, this tells whether the shift to newHeadAddress was successfully registered with FASTER</returns>
public bool ShiftHeadAddress(long newHeadAddress, bool wait)
{
// First shift read-only
// Force wait so that we do not close unflushed page
ShiftReadOnlyAddress(newHeadAddress, true);
// Then shift head address
if (!fht.epoch.ThisInstanceProtected())
{
fht.epoch.Resume();
var updatedHeadAddress = allocator.ShiftHeadAddress(newHeadAddress);
fht.epoch.Suspend();
return(updatedHeadAddress >= newHeadAddress);
}
else
{
var updatedHeadAddress = allocator.ShiftHeadAddress(newHeadAddress);
return(updatedHeadAddress >= newHeadAddress);
}
}
/// <summary>
/// Shift log head address to prune memory foorprint of hybrid log
/// </summary>
/// <param name="newHeadAddress">Address to shift head until</param>
/// <param name="wait">Wait to ensure shift is registered (may involve page flushing)</param>
/// <returns>When wait is false, this tells whether the shift to newHeadAddress was successfully registered with FASTER</returns>
public bool ShiftHeadAddress(long newHeadAddress, bool wait)
{
// First shift read-only
ShiftReadOnlyAddress(newHeadAddress, wait);
// Then shift head address
fht.epoch.Resume();
var updatedHeadAddress = allocator.ShiftHeadAddress(newHeadAddress);
fht.epoch.Suspend();
return(updatedHeadAddress >= newHeadAddress);
}