configure memory now selects the ssd engine for transaction log spilling #1314
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…ing. Transaction log spilling is only used when the transaction logs cannot keep all of the unpopped mutations it has in memory. If we are only using this data structure because we do not have enough memory, it is much less safe to use the memory storage engine for this purpose.
ajbeamon
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Mar 18, 2019
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Have we tried this out at all to see what will happen if it's is used on a spinning disk? I'm a little concerned that the act of spilling in that scenario isn't going to behave very well. Certainly it's better than becoming unrecoverable, but the advantage the old scheme has is that it would be capable of absorbing periods of spilling that are limited in duration. Since this change may not be a pure win, I think we should understand what downside it's going to have. It may also ultimately mean that we make it easy to configure both behaviors and tone down our warning message about using the new one.
ajbeamon
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Mar 18, 2019
This was referenced Mar 19, 2019
etschannen
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Mar 26, 2019
configure memory now selects the ssd engine for transaction log spilling
etschannen
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Mar 26, 2019
configure memory now selects the ssd engine for transaction log spilling
alexmiller-apple
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Mar 26, 2019
configure memory now selects the ssd engine for transaction log spilling
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Transaction log spilling is only used when the transaction logs cannot keep all of the unpopped mutations it has in memory. If we are only using this data structure because we do not have enough memory, it is much less safe to use the memory storage engine for this purpose.