// TODO: This should be part of buffer pool class.
// Ideally page manager shouldn't keep track of in memory-disk mappings.
private async Task RecordUsageAndEvict(ulong pageId, ITransaction tran)
{
ulong[] pageIdsToEvict = this.bufferPool.GetEvictionPolicy().RecordUsageAndEvict(pageId).ToArray();
foreach (ulong pageIdToEvict in pageIdsToEvict)
{
if (tran.AmIHoldingALock(pageIdToEvict, out LockTypeEnum heldLockType))
{
// If this page is needed for myself don't release the lock.
// Just ignore for now.
continue;
}
using (Releaser lckReleaser = await tran.AcquireLockWithCallerOwnership(pageIdToEvict, LockTypeEnum.Exclusive).ConfigureAwait(false))
{
logger.LogDebug($"Evicting page {pageIdToEvict}");
IPage pageToEvict = this.bufferPool.GetPage(pageIdToEvict);
// Somebody came before us and evicted the page.
if (pageToEvict == null)
{
continue;
}
await this.FlushPage(pageToEvict).ConfigureAwait(false);
bufferPool.EvictPage(pageToEvict.PageId(), pageToEvict.GetBufferPoolToken());
logger.LogDebug($"Page {pageIdToEvict} evicted from buffer pool and flushed to the disk.");
}
}
}