duplicati/Duplicati/Library/Main/Operation/Restore/DeadlockTimer.cs

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// Software is furnished to do so, subject to the following conditions:
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#nullable enable

using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace Duplicati.Library.Main.Operation.Restore
{
    /// <summary>
    /// Class for keeping track of the maximum processing time of a block
    /// request making a roundtrip to/from the BlockManager.
    ///
    /// The times are not Interlocked as reads and writes are atomic for int
    /// types and exact accuracy is not required.
    ///
    /// https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/language-specification/variables#96-atomicity-of-variable-references
    ///
    /// The worst case is that the reads are stale by one update, which is
    /// acceptable for this use case. The same applies to the MaxProcessingTime
    /// property, which means that the BlockManager may use a slightly stale
    /// value when checking for timeouts, which is also acceptable.
    /// </summary>
    internal class DeadlockTimer
    {
        /// <summary>
        /// The log tag for this class.
        /// </summary>
        private static readonly string LOGTAG =
            Logging.Log.LogTagFromType<DeadlockTimer>();

        /// <summary>
        /// Initial threshold (in milliseconds) for detecting deadlocks.
        /// </summary>
        public static int initial_threshold =
            (int)TimeSpan.FromMinutes(5).TotalMilliseconds;

        /// <summary>
        /// Maximum processing time (in milliseconds) recorded for any block
        /// request.
        /// </summary>
        public static int MaxProcessingTime = initial_threshold;
    }
}