1. A method implemented by data processing apparatus, the method comprising: obtaining, during a current editing session, textual input provided to a document editing application by a user associated with a user device, the textual input being provided to the document editing application for inclusion in a document; receiving textual suggestions from a suggestion model based on the obtained textual input, each textual suggestion comprising one or more words to be suggested for inclusion in the document, each textual suggestion having a confidence score; providing, during the current editing session and not to the user, respective textual suggestions having confidence scores above a current threshold value; identifying, during the current editing session, one or more performance measures associated with the current editing session for the document, each performance measure being at least one of a typing speed of the user or a latency of the user device based on session data obtained during a document editing session, the session data being for the obtained textual input and prior texts included in the document prior to the obtained textual input; providing the one or more performance measures as input to the suggestion model that was trained using historical performance measures identified in performance logs for a plurality of historical document editing sessions of a plurality of users prior to the current editing session; generating a modified threshold value based on the inputted one or more performance measures, the modified threshold value different from the current threshold value; and throttling the textual suggestions during the current editing session by providing, during the current editing session and to the user, at least one of the respective textual suggestions having a confidence score above the modified threshold value.